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                           Mineral of the Month--May

                           Dolomite as Host to Herkimer Diamonds

                                           Calcium Magnesium Carbonate hosting Silicon Dioxide

                              CaMg(CO3)hosting SiO2

                                       Dolomite: Dolostone & Herkimer Diamonds, Part 2

                              By Ken Casey

Chemistry & Science
Dolostone Geology
Niagara Escarpment
Erie Canal
New York Karst Caves
Herkimer Diamonds
Metaphysical Properties
Local Quartz
Until Next Time
Article Contributors
Photo & Graphics Credits
Suggested Reading
Invitation to Members
Past Minerals of the Month
lock60-7.jpg (319277 bytes)
Erie Canal Lock No. 60 at Macedon, NY
Photo by Frank E. Sadowski, Jr.   2005
lockport_dolo1.JPG (1727 bytes)
lyons_dolo3.JPG (1208 bytes)
herkimer_dolo2.JPG (1558 bytes)

Dolomite, as Dolostone hosts many minerals...


fullherks-17_f.jpg (34121 bytes)   ...especially Herkimer Diamonds!

The above image is courtesy of Ted & Anita Smith of the Ace of Diamonds Mine 2005


  This is the second article in a two-part series on Dolomite.   Last month, in part 1, we explored
Dolomite and Dolostone as host to dolomite crystals.   This month, we will investigate the world
of Herkimer Diamonds, the doubly-terminated, clear quartz crystals found in vugs therein.

     Our journey will take us over the Niagara karst in the western part of New York State, along the
Erie Canal, to the Herkimer area near the center.  As an aside to karst, we will mention some
nearby caverns to visit.  Pull out your camera, as we will stop at a couple of scenic locks along
the way. 

     We will discuss theories of Herkimer diamond formation and visit several locales for collecting. 
Most are “fee-mining” locations that require you pay a modest fee to collect and mine.  I will link
to these sites, so that you may prepare your own collecting excursions later.

     After collecting, we will traverse the canal a little further down to Albany.  If you would like to
take a boat along the Hudson River to New York City on the way back to our clubhouse, be my

     So saddle up!  The caravan is ready to take-off!  Oh, and don’t forget your hardhat!


    We begin at around the Niagara Escarpment, then ‘shuffle down to Buffalo’ (forgive the pun) to
launch upon the Erie Canal.  Our first stop is at Lockport, New York.  We will stop is at various locks
and ports along the way. Our next itinerary destination is to classic Herkimer Diamond mines in and
around Herkimer, New York.  Our last stop is at Albany, New York (the state capital).

     Since our driver is weary from last month's trip, we have decided to hire a boat to take us the
length of the Erie Canal.

     Well, we are all here.  Everyone has their safety and mining gear, and we have all met up on
time on the Niagara Escarpment.  We will tour both the Canadian and American sides, then boat down
to the Lake Erie entrance of the Erie Canal in western New York.  All aboard!


Chemistry & Science


     Last month we had discussed the many uses, both practical and recreational, of dolostone and
karst topography.  So, this month, we will cut soon to the chase of collecting Herkimer Diamonds! 
To prepare us for good hunting, we will view dolostone across the state of New York, beginning at
the Lockport Formation, which underlies both New York State and Ontario, Canada.  Our discussion
begins with the New York karst, then continues with our visit to the Niagara Escarpment at Niagara
Falls, Ontario, Canada.  Of course, a better understanding of karst geology will aid us in our quest. 
Let's go!

Dolostone Geology

New York Karst

     New York State has known, exposed areas of karst topography (limestone/dolostone).  As an
amazing coincidence, the Erie Canal, Mohawk River Valley, and Hudson River Valley cut right
through these geologic layers.  Well, maybe not such a coincidence, as nature has found the path
of least resistance by pulling rainwater downwards to erode the softest layers of rock first: the New
York karst.  And, geologists, engineers, and workmen have discovered to the opposite, by virtue of
their goal to dig a canal, the path of greatest resistance.  That is perhaps why nature did not create
the west-east ‘Erie River’ first.  That is one reason why Governor DeWitt Clinton’s detractors called
his massive project “Clinton’s Folly”. 

     This author applauds all those who have made the canal possible—as it is a grand achievement! 
All of my testimony here will add the to positive reputations of both nature and resounding human
accomplishment.  So, let’s begin our tour!

     After we cross the Niagara Escarpment, we can follow roughly the towpath of the hard won Erie
Canal.  It’s your choice whether you wish to hike, or to ride in the canal boat.  No worries, we will
wait for you at the next pit stop.

buffalo_skyline.jpg (52428 bytes)
Buffalo, New York Skyline

     Our canal tour will begin at Buffalo, New York at the Lake Erie entrance to the Erie Canal.   

     We end at Albany, New York at the Hudson River entrance to the Erie Canal. 

     I’ll be handing out a karst and canal map of New York State, which point out our stops.  To
research your own karst-only maps, visit the NYSDEC Mineral Resources Environmental Navigator
Interactive Map.

ny_karstmap1b.JPG (25274 bytes)
Karst Map of New York State as derived by the NYSDEC Environmental Navigator Interactive Map

    To help envision the work that went into carving the canal, picture workers blasting dangerously
with only black powder and cutting the hard Lockport Dolostone with hand tools to build the canal
locks and town buildings.  We will visit their surviving works to compare dolostone along the way.

Lockport Formation

Minerals of New York’s Lockport Formation
Lockport Cave Raceway Tour, Lockport, NY (Erie Canal)
Lockport Cyber Museum of Rocks, Minerals & Fossils

lockport_fm.gif (12021 bytes)
The Niagara Escarpment is topped by the Lockport Formation

     To be specific, the Lockport Formation is the geologic layer that covers part of western New York
State, and is accessible to surface mining.  As a source of dimension stone for building, it has served
many New York cities, towns, and canal-builders.  In fact, the hard Lockport Dolostone had to be
blasted and cut to make many of the canal locks feasible.  This task was more difficult as dynamite
was not invented until the 1860's.  Alfred Nobel's invention did help in later canal expansions and in
quarrying rock.

     To be sure, “[t]he Lockport Formation is an ideal resource for the mineral industry of the region.
There are four active quarries in the Lockport Group: Redland quarry in Niagara Falls, Redland quarry
in Lockport, Dolomite Products quarry in Penfield, and Dolomite Products quarry in Walworth, New
York. Over the years, these locations have yielded a variety of interesting mineral specimens...”[i]

     Our focus on this trip is to visually sample dolostone across the canal project and finally to collect
the world-renowned quartz crystals, known as ‘Herkimer Diamonds’.

Niagara Escarpment

     To understand the range of dolostone across the state, we will need to stop and visit several locales
along the way.  For an easy primer in dolostone stratigraphy, we only need to look upon the Niagara
Escarpment at Niagara Falls.

     The Niagara Escarpment is a grand geological feature that spans across two countries: The United
States and Canada.  As this wonder has captured the native interests of industry, residence, and
conservation over history, a movement in recent decades has been successful in conserving and planning
for land use.  That is how we get to study the preserved geological features.  By visiting many of the
conservation and park areas in Niagara Falls, Ontario and around Niagara Falls, New York, we can better
comprehend the formation and erosional processes.  As our trip will take a few days, let’s start with
lunch here, at one of these parks, shall we?

     This author has located three groups whose mission supports the optimal recreational and business
use of this feature in the Canadian province of Ontario.  Over our meal we can discuss them. They are:

Escarpment Centre Ontario
Coalition On the Niagara Escarpment (CONE)
Ontario’s Niagara Escarpment

     Continuing on, we can see that business use includes the quarrying of limestone and dolostone at
the Dufferin Aggregates Quarry in Milton, for example.  Recreational pursuits abound at the preserved
UNESCO World Biosphere sections, such as hiking, birding, and nature photography.

Photo_Quarry.jpg (26250 bytes)
Limestone Quarry, Dufferin Aggregates (NEC)
Photo courtesy of CONE    2005

     As we cross the Rainbow Bridge in the United States, we enter Niagara Falls State Park, the oldest
state park in America (1885).  It was won by citizens who formed the “Free Niagara” movement, led by
famous New York City Central Park’s architect, Frederick Law Olmsted.”[ii]

     The National Park Service is conducting a study to preserve parts of the Niagara Falls area nationally
“[a]t the initiative of Senators Charles Schumer (D-NY) and Hilary Rodham Clinton (D-NY), and
Representative John LaFalce (D-NY), Congress in 2002 passed a law directing the National Park Service
to "conduct a study of the suitability and feasibility of establishing the Niagara Falls National Heritage
Area in the State of New York."[iii]

     The result could support the study of the geology in a preserved setting.


Niagara Escarpment Geology Study & Conservation

     The difference in topography height above sea-level separates the two part of the escarpment.  The
upper part lays mostly in Ontario, Canada, the lower part in New York State.  The best known example
of this disparity is Niagara Falls, whose waters fall over the edge of this cuesta.

     Wondrous amounts of tan dolostone are naturally displayed along the Niagara River along the Niagara
Gorge.  This author was fortunate enough to purchase a core-drilling sample from the 1969 engineering
project to investigate “repairing” the falls.  (see: below)

     A geological history of the Falls can be found at Origins of Niagara - A Geological History.

niagaracore1a.jpg (50557 bytes) niagaracore2.jpg (80518 bytes)
Niagara Falls Core Sample, Dolostone
Niagara Falls Core Sample, Dolostone
(side view)
Photos by Ken Casey from personal collection  2005

     Upon visiting Ontario, you may see signs welcoming you to the Niagara Escarpment. “Here you will
learn about plans to build a world class interpretive centre called Escarpment Centre Ontario (ECO), just
south of Owen Sound, Ontario. The site is on Conservation Authority land and near the famous
Bruce Trail.

road_sign_photo.jpg (87595 bytes)

Phase 1: Come and visit a mini version of ECO at the Inglis Falls Conservation Area. The old mill building,
situated just on the edge of the falls, will feature static and interactive displays on the flora, fauna, geology,
and people of the Niagara Escarpment and give you
just a small taste of what’s to come.”[iv]

     Hiking is the best way to observe dolostone
geology.  Let's go!


Photo_Niagara_Gorge.jpg (31503 bytes) Photo_Georgian_Bay.jpg (28711 bytes) Photo_Mono_View.jpg (27488 bytes)
Niagara Gorge
Georgian Bay
(Jasna and Goran Holjak)
Mono Cliffs View
(Jasna and Goran Holjak)
Photos courtesy of CONE  2005

     The Coalition on the Niagara Escarpment (CONE) protects the geology in its Niagara Escarpment
World Biosphere Reserve (WBR).  A WBR is what “[t]he United Nations Educational, Scientific and
Cultural Organization (UNESCO) through its "Programme on Man and the Biosphere" (MAB) recognizes
certain regions as having global, as well as regional or national significance.”[v]

     Under Ontario law, CONE focuses upon “the green corridor 725 kilometres long from Queenston
near Niagara Falls on the Niagara River past Cabot Head to Tobermory, at the tip of the Bruce Peninsula.” 
Put succinctly, “[t]he Niagara Escarpment's value to Ontario society lies partly in its economic potential -
in other words, the value of extracting its resources together with that of retaining natural areas for
recreational purposes. But the Escarpment's value also lies in its simply being there, whether humans
make use of it or not. As the last, essentially continuous forested corridor in southern Ontario, it holds
tremendous ecological significance and has much to teach us about nature.”[vi]

     The third organization, The Niagara Escarpment Commission, was formed under “The Niagara
Escarpment Planning and Development Act and the Commission provide for the maintenance of the
Niagara Escarpment and land in its vicinity substantially as a continuous natural environment.”[vii]

     The folks in Ontario seem to be serious about planning and preservation.  For them to offer us a
place to study Canadian geology, I applaud their diligence.  As these are protected areas, much like
our national parks, no collecting of minerals is generally permitted.  On our virtual tour of the area,
please do take as many “photo samples” as you wish.


Photo_Cataract_Falls.jpg (8447 bytes) Photo_Flowerpot_Island.jpg (9950 bytes)
Cataract Falls,
Flowerpot Island,
Fathom Five National Marine Park
Photos courtesy of CONE  2005

Niagara Escarpment Geology


     Before we can appreciate dolostone fully, we are prudent to study its geologic history.


     “The Niagara Escarpment is a geologist's paradise and contains some of the best exposures of
rocks and fossils of the Palaeozoic Era found anywhere in the world.


     As a landform, the Escarpment began to form only after the ancient sea withdrew some 300
million years ago.


     Over succeeding millions of years erosive agents slowly removed the softer shales underlying the
more resistant dolostone layers.


     As the softer underlying material was eroded away , large blocks of the resistant dolostone caprock
broke off creating the vertical face of the present day Escarpment.”[viii]


     As the Niagara Escarpment formed during the receding of water, so does the Niagara River perform
that natural function today.  Granted, the river flows forward, and the land recedes at the Gorge, but the
area remains a water-formed feature today.  It has been studied by even the earliest geologists.


     “The Geological Survey of Canada first referred to the Niagara Escarpment in 1864, identifying it as
a ‘step in the countryside.’ It is a complex land form consisting of sedimentary bedrock of marine origin
overlain by glacial deposits.  The limestones, dolostones, shales and sandstones of the Niagara
Escarpment bedrock date from the Ordovician and Silurian Periods of the geological time scale. They
were formed between 425 and 450 million years ago. But it would be a mistake to say that the
Escarpment was formed during this time, for the Escarpment we see today is the result of erosion that
has occurred over the last 250 million years or so.  The Niagara Escarpment is not the result of a fault
(a fracture in the earth's crust), as some escarpments are, but instead is a "cuesta" which was formed
by differential erosion. Simply put, this means that underlying, soft rocks (shale) eroded away relatively
quickly and the more resistant caprock (limestone and dolostone) was undermined and broke off,
creating a cliff-like slope.  Formation of the Escarpment began somewhere to the north and east of its
present location. Through continuous erosion, it receded to its current position and became the dominant
feature of the southern Ontario landscape.”[ix]


     Simply put, “The Niagara Escarpment, as a feature of geography is a long escarpment or cuesta
running through southern and central Ontario, Canada and western New York in the United States. It
is composed of the Lockport geological formation of Silurian age, and is similar to the
Onondaga geological formation which runs parallel to it and just to the south in New York and eastern
Ontario. The escarpment is the cliff over which the Niagara River flows to create Niagara Falls.”[x]



Erie Canal

     Now that we know a little more on dolomite/dolostone geology, let’s head south to Buffalo,
New York.  Here, from the western entrance of the Erie Canal, we can study dolostone of different
colors along the way.  Generally speaking, the dolostone starts out as gray, and weathers to brown. 
So, keep your eyes peeled.

     This 360 mile (580 km) long man-made waterway spans from Lake Erie to the Hudson River. 
It traverses karst terrain over most of its length to bridge topography that differs by 571 feet (174 m)
from end to end.[xi]  


erie_canal_profile2.gif (2848 bytes)
Erie Canal Western Topographic Profile from Buffalo (west) to 100 miles before Albany (east)

Drawing by Ken Casey    2005

     To employ a different sense in our discovery, “[r]un a finger along a raised-relief map of the eastern United States to find the notch in upstate New York where the Mohawk River cuts eastward through the Appalachian Mountain Range. That gap separating the Catskills from the Adirondacks, the only such opening from Maine to Alabama, could hold a canal between the Hudson River and Lakes Ontario and Erie.”[xii]  I am impressed with the non-aerial surveys of the time that supported planning of the canal
path.  To decide on over 70 locks to be originally built must have been an engineering challenge of the

nystate_eriecanalmap2.gif (6140 bytes)
Drawing by Ken Casey   2005

     Called “Clinton’s Folly” during construction in 1825, New York Governor Clinton had the last
laugh,as the project paid for itself in ten years of operation, and still has use today![xiii]

     It seems that a successful project of dolomite has helped the economy and culture of New
Yorkers to advance.  Momentous architecture in Syracuse, for example, highlights this fact.

locks-1915.jpg (161541 bytes)

     “Within 15 years of the Canal's opening, New York was the busiest port in America, moving tonnages greater than Boston, Baltimore and New Orleans combined.The impact on the rest of the State can be seen by looking at a modern map. 

     With the exception of Binghamton and Elmira, every major city in New York falls along the trade route established by the Erie Canal, from New York City to Albany, through Schenectady, Utica and Syracuse, to Rochester and Buffalo.  Nearly 80% of upstate New York's population lives within a 25 miles of the Erie Canal.”[xiv]

Antique Postcard of the Locks [Upper Level] at Lockport, NY
Courtesy of Frank E. Sadowski, Jr.

     As a result, commerce extended across the state, thus growing cities along its route. 
Today, a visitor may tour many of the locks and canal museums, and even take historic boat,
trolley, and towpath tours. 

     If one travels the length of the canal, one can witness the varying shades of tan and gray
rock exposed to show the state’s karst topography.  To rockhounds, the view of exposed
dolostone used in its construction can be a treat.  I'll be taking digital photos for sharing later.

lockport_dolo1.JPG (1727 bytes) lyons_dolo3.JPG (1208 bytes) herkimer_dolo2.JPG (1558 bytes)
Lockport Lyons Herkimer
Dolostone variations across the Erie Canal (west to east)

 [picture of dolostone varieties & Sadowski pix]

     Officially, the full-length of the canal, as used for commerce, stopped in 1917 with the
advent of the railroads.  Some of the machinery and lock installed by the completion in 1918
of the widening project are fully-functional at the writing of this article.  Portions are still used
today.[xv]   Today, the railroad and modern highway system has supplanted the canal's full
function, though commerce is still practiced along its banks.

     Many towns along the way either have or have plans to intend restoration of locks and for
improvement of the banks to support recreation.  One example is the Village of Pittsford. 
Their proposed Canal Project incorporates boat docks, walkways, and a pavilion.

     With the wisdom of experience, even President Thomas Jefferson praised its original
construction, as many mariners and boaters might praise it recreational value today. 
"’(The Erie Canal) will bless (New Yorkers) with wealth and prosperity, and prove to
mankind the superior wisdom of employing the resources of industry in works of
improvement rather than of destruction.’-- Thomas Jefferson, June 8, 1826.”[xvi]

     I don't know what Theodore Roosevelt had to say in the early 1900's about this or its
planned expansion, as he was also involved in the work of another project: The Panama
Canal.  He did make popular the palindrome phrase "A Man, A Plan, A Canal, Panama",
which some former school children remember to this day (me included).

     The 1903 “Barge Canal” expansion project plans were to add capacity for larger boats. 
“The resulting canal was completed in 1918, and is 12 to 14 feet deep, 120 to 200 feet wide,
and 363 miles long, from Albany to Buffalo. 57 Locks were built to handle barges carrying up
to 3,000 tons of cargo, with lifts of 6 to 40 feet. This is the Erie Canal which today is utilized
largely by recreational boats rather than cargo-carrying barges.”[xvii]

Lock17-1928.jpg (180672 bytes) Lock-E17-2.jpg (184965 bytes)
Antique postcard by Chas. Hughes, postmarked 1928
Lock No. 17 Erie Canal, Mohawk River, Little Falls, NY
Antique aerial photo of existing view
Courtesy of Frank E. Sadowski, Jr.

     As the official canal boating season begins around the beginning of May, you may wish to
consult the New York State Canal System's Notices to Mariners Page for openings news,
before you go.  You can even purchase a recreational boating pass from the official
New York State Thruway Authority Headquarters in Albany to traverse the canal.  You could
even sing The Erie Canal Song enroute, if you like.

     You could drive Interstate 90, take the Amtrak Empire Service Route, or mosey on down
the canal by boat.  Or visit the Erie Canalway National Heritage Corridor run by the National
Park Service.  So, we will “shuffle on down to Buffalo” for dinner, then catch our boat for Lockport.

Lockport, New York

     We’ve reached our destination for the evening.   We’ll stay over, then get a fresh start in
the morning to study the canal and its towns.  For tonight, here’s some reading that will
prepare you:

     Finishing the sections through the dankest swamps, “[a]fter Montezuma, the next
obstacle was crossing the Niagara Escarpment, an 80-foot (24m) wall of hard dolomitic
limestone, in order to rise to the level of Lake Erie. The route followed the channel of a
creek that had cut a ravine steeply down the escarpment, with five locks in a series, thus
giving rise to the community of Lockport, New York. The final leg of the canal had to be cut
as much as 30 feet (9m) through another limestone layer, the Onondaga ridge. Much of that
section was blasted with black powder. The inexperience of the crews often led to accidents,
and sometimes rocks falling on nearby homes.”[xviii]

120694pv.jpg (162782 bytes) 120695pv.jpg (96066 bytes)
NY-61-5: Lockport, NY NY-61-6: Lockport, NY
Courtesy of Frank E. Sadowski, Jr.
[Photos by J. Carl Burke, 1971HAER No. NY-61]

Other Locks & Ports

     There are many ports served by the Erie Canal and its branches.  Among them are:
Rochester, Syracuse, Rome, Lyons, Amsterdam, Schenectady, and Little Falls.  We will
pause at the occasional lock and port to sample the dolostone construction.  Our terminal
pit stop will be at Little Falls to learn of and collect Herkimer Diamonds and Little Falls
Diamonds.  As we will cover about 200 miles along the way, we will take a couple of
overnights at scenic towns along the way.

     Before we go, note the gray-tan dolostone blocks used to make these aqueducts:

9MileCreekAqueduct-5.jpg (478521 bytes) aqueduct-2.jpg (378587 bytes)
The Nine Mile Creek Aqueduct at Camillus Erie Canal Park Aqueduct at the
Chittenango Landing Canal Boat Museum
Photos by Frank E. Sadowski, Jr.    2005

Village of Lyons, NY
The Erie Canal: A Journey Through History (Virtual photo tour)
Medina Railroad Museum (Canal rail excursions)
Lockport's Towpath Trolley Tour
Grayline Erie Canal and Locks Tour


Petrographic Analysis

     For the intervening evenings, here is some reading on dolostone textures.  If you
would like to study some of the petrographic analyses available for some of New York’s
dolomite/dolostone, I suggest you review the six textures of the Beekmantown Group in:


by Mossbah M. Kolkas and Gerald M. Friedman.

New York Karst Caves

     By now, I am thinking that you have had your fill of dolostone after traveling hundreds
of miles along the canal.  You may have even learned all the verses of The Erie Canal Song
So, to add some pop to our excursion, let’s revisit caving!

    herkimer_and_cave_sites2.GIF (14399 bytes)

      “In the northeast United States, there are several different types of karst areas. The
Adirondacks and New England including that part of New York east of the Hudson River
contains metamorphic rocks and most caves there are found in marble. The remainder of
New York has mostly sedimentary rocks and most caves in that area are found in limestone
and dolostone.

     Most of the longest caves in New York and New England are found in Albany and Schoharie
Counties and in Jefferson County near Watertown, NY. All of these are formed in limestone.
The three longest caves in the northeast are found in Schoharie and Albany Counties. The
longest is over 6 miles long.

     There are a few long marble caves found in the Adirondacks and in western New England.

     However, in these areas, the marbles tend to occur in valleys in isolated pockets or outcrops.
The only significant exposures of soluble rock in eastern New England is found in northern Maine.
Some caves are known, but the area has not been well explored.”[xix]

     New York State boasts several karst caves, many of which are famous tourist destinations. 
As this is a side-trip, I am leaving you to your own devices to choose which of these underground
hollows to explore.  When you are done, just meet back up at the highest lift lock on the canal,
Lift Lock 17 at Little Falls, and we will continue our journey to Herkimer.  We may need to portage
on occasion, much like the Yukon gold miners, but the exercise will do us good.


New York Museums: Albany

     In addition to fine spelunking, New York offers many museums touting geology or canal
exhibits for the whole family.  One such place is The New York State Museum in Albany.  

     There are two ways to view the Herkimer Diamond Collection at The New York State Museum
in Albany, New York.  One is to visit in person.  The other is to review the Virtual Mineral Exhibit
online.  There you will find minerals of the Little Falls Dolostone and the Lockport Formation,
among others.  A virtual visit during one of our pit stops could inspire you. 

17738.jpg (104953 bytes) 17739.jpg (162277 bytes) 19327.jpg (136017 bytes)
Selenite & Dolomite Crystals Red Sphalerite & White Calcite Fluorite Crystal
"Minerals of the Lockport Formation"
Photos courtesy of Dr. Marian Lupulescu, NYSM  
Photos by Erik Rutnik      2005

Little Falls Dolostone

     Little Falls Dolostone plays host to many minerals, the most famous being "Herkimer" or
"Little Falls" Diamonds.  These quartz crystals formed some 500 million years ago in the Upper

     "The Little Falls Dolostone formed at roughly the same time as the dolostone of the Whitehall
Formation, and is also as part of the carbonate shelf deposits.  However, the Little Falls exhibits
some significant differences that undoubtedly led stratigraphers to map it as a different unit.  
Firstly, it contains more silt than the Whitehall dolostone, indicating a closer proximity to the
shoreline.  More importantly, hot, silica-rich and hydrocarbon-bearing fluids extensively invaded it
shortly after its deposition.  The hydrocarbons from the fluid formed a mineral called anthraxolite,
and asphalt-like substance.  The silica from the fluids formed quartz crystals in the fractures and
cavities of the rock.  These quartz (SiO2) crystals, called Herkimer Diamonds, are sought after
by mineral enthusiasts for their size, clarity, and doubly terminated habit (quartz crystals rarely
exhibit two points, such as these).”[xx]

     There are other minerals to be found hosted in the Lockport Formation dolostone.  They are:
fluorite, celestite, calcite, galena, gypsum, and sphalerite.[xxi]

    Dr. Marian Lupulescu, Associate Scientist and Curator of Geology of the New York State
has kindly allowed us to borrow some his minerals for our virtual tour.

H353.jpg (112490 bytes) H364.jpg (90605 bytes) H351.jpg (107773 bytes)
Herkimer Diamond cluster Large Calcite crystal Calcite & Dolomite Crystral Vug
"Minerals of the Little Falls Dolomite"
Photos courtesy of Dr. Marian Lupulescu, NYSM
Photos by Erik Rutnik      2005

Herkimer Diamonds

     Now that we’ve covered miles of karst and dolostone along the Erice Canal and in local caves,
we are ready to learn more about the formation, mining, and collecting of Herkimer Diamonds!

Herkimer.gif (3000 bytes) Herkimer2.gif (2934 bytes) Herkimer3.gif (2313 bytes)
Herkimer Diamond Crystals
Drawings by Ken Casey   2005

What is a Herkimer Diamond?

     A Herkimer Diamond is not a diamond, as the name denotes, but a naturally fine-
faceted quartz crystal that looks like a finished cut diamond.  Gem lore has it that
General Nicholas Herkimer was presented some of these specimens by his soldiers
during the American Revolutionary War.  Curious to know if they were real carbon
diamonds, he sent them to be tested.  Disappointed that he could not help finance
the struggling troops with them, he went on to serve with honor.  The town and county
of Herkimer bear his name.

fullherks-08_f.jpg (35001 bytes) fullherks-15_f.jpg (42200 bytes) fullherks-16_f.jpg (33965 bytes)
Herk from Ace of Diamonds Mine Twinned cluster herk Doubly-terminated herk
Herkimer Diamonds from the Ace of Diamonds Mine
Photos courtesy of Ted & Anita Smith    2005

     I don’t know about you, but I don’t mind being fooled by their crystalline beauty. 
Then again, I like to collect pyrite crystals (fool’s gold).  The value in my eyes is of the
natural beauty and order of the facets.  As one might offer that ‘beauty is in the eyes
of the beholder’, of course, it is your choice as to what you admire about this quartz

     If you came on this fieldtrip with us, I would imagine you could appreciate these
diadems, as much as you admire dolostone.

     So, let us define this natural wonder.  As we know, pure quartz is silicon dioxide
(SiO2).  We find most Herkimer Diamonds to be clear and colorless, therefore, pure
quartz it is.  Some crystals exhibit anomalies, such as ‘enhydros’ and ‘carbon spots’. 
But, more on that later.

     Sometimes crystals form as a druze inside the vug lining.  Other times it forms as
either singly- or doubly-terminated crystals.  There are many variations on facet angles,
however, the most common arrangement has eighteen (18) sides with two terminal points.

How are Herkimer Diamonds formed?

     The quartz is a secondary formation to the internally-created karst erosion that formed
the vugs in the first place.  One might think of the vugs as ‘mini caves’.  In lieu of
speleothems, crystals of dolomite and quartz form.

     There are many theories of formation, including one purported by Mr. Barry S. Moore
in his book Herkimer Diamonds: A Complete Guide for the Prospector and Collector.  He
suggests that marine invertebrate fossils, called Radiolarians, which are rich in silica, are
the source of materials for nature to construct Herkimer Diamonds.  As so many elements
and compounds are deposited on the sea-floor during limestone/dolostone formation, this
author tends to accept his theory as correct.  At least, for our purposes, this plausible
theory can get a our group discussion started can add to the science and lore of our
collecting experience.

FALLS3.jpg (20906 bytes) FALLS1.jpg (26685 bytes) H360.jpg (97945 bytes)
Scepter Smoky Skeletal
"Minerals of the Little Falls Dolomite"
Photos courtesy of Dr. Marian Lupulescu, NYSM
Photos by Erik Rutnik      2005

What kind of crystal anomalies might we find?

     Enhydros, hydrocarbon spots, and phantoms are among the more rare variations of
this area’s special quartz crystals.  Twins, clusters, scepters, and tabulars make up the
range of outstanding forms to be found.  Smoky quartz, color veils, and skeletals can all
be shown by applying lighting.  The varying guises of this highly-prized New York quartz
can draw a rockhound to populate his or her collection with nothing else. 

     If I lived closer to New York, or had my own claim, like my fellow club member Erie
Meier, you might not see me for weeks at a time, unless, of course, we worked the
claim together!

Where can we find Herkimer Diamonds?

     Most anyplace where conditions existed to have created these vuggy gems, one can
find them.  If you refer to the map above, showing karst exposures in New York state,
there is a good chance that many of them could yield these faceted quartz prizes.  One
caution though: If you go prospecting, be sure to gain permission from the land-owner,
before digging in his or her backyard.  In my personal experience, I have found that most
folks are friendly, and a rare few will let you dig.  To be sure of a successful collection
effort, though, I recommend visiting the fee-mining areas first.

Crystal_Grove_ledge.jpg (148171 bytes)

Crystal Grove wall

Herkimer_Diamond_Mine_ledge.jpg (142118 bytes) Herkimer Diamond Mine wall
Treasure_Mountain_ledge.jpg (103739 bytes)  

Treasure Mountain wall

Photos by Ken Casey 2005

     There are at least six locations that this author knows, and has mined at four of them. (*)
I would like the visit the other two one day.


     Ted Smith, owner of the Ace of Diamonds Mine in Middleville, New York, recently told
me that “We occasionally find really world class dolomite crystals with Herkimers.”  In
1999, this author mined there and found some nice tan, saddle-shaped crystals lining a
partial vug.  Though I didn’t work ‘the wall’, I did come away with some 1-inch long (from
point-to-point) complete Herkimers.  My wife and I were so impressed, that we bought
Ted & Anita’s official matching orange t-shirts to war and invite queries.

herkimer2.jpg (67823 bytes) herkimer1.jpg (62377 bytes)
Tan Dolomite Crystal Vug Author digging at Ace of Diamonds
Photos by Ken & Eileen Casey  1999-2005

     All of our hosts on previous excursions have been pleasant, knowledge, and helpful. 
We would re-visit any and all of them.

     As a guide of where to visit, stay, and dine, visit the Herkimer County Chamber of Commerce
Or, check out each mine’s website; many offer onsite camping, if you prefer.  Personally, I like camping—less walk to the dig!


Mining & Collecting

     Now for the digging!  Depending on your bent for breaking hard rock, as a collector,
you have many choice methods for finding prized Herkimer Diamonds.  If you choose to
just gather crystals washed by the rains, then more power to you.  Sometimes kids find
the best, freed-up herks this way.  My theory is that since their eyes are closer to the
ground, they tend to spy the glittery specimens before others, therefore, more fun for
the family or group.

     If you would like to escalate the search process, then screening may be for you. 
By taking a wooden-framed wire-mesh screen along, sifting for loose diamonds can go
a lot faster.  Some folks prefer dry-screening, whereas others choose water and
wet-screening.  Some mines will rent equipment to you, at others, you must bring your own. 
The first three in my list, Crystal Grove, Herkimer Diamond Mine, and Ace Of Diamonds do
rent tools and screen boxes for a modest fee.  I occasionally rent to save space in my
vehicle for more diamonds!

fullherks-23_f.jpg (50354 bytes) screenbox2.gif (1988 bytes) fullherks-13_f.jpg (58723 bytes)
Iron-oxide coated 'herks' Screen Box Pristine Herkimer crystals
Photos courtesy of Ted & Anita Smith, The Ace of Diamonds Mine, Middleville, NY   2005

Drawing by Ken Casey   2005

     For the stout-hearted, hard-rock mining just might be for you.  Various tools,
methods, and secrets could beckon you to the lore of releasing the most pristine,
vug-enclosed crystals for your collection. 

     Some miners elect to employ spring steel bars and heavy sledge hammers to work
away at the wall of dolostone.  Searching in just the right place in the stratigraphy could
just land you into a celebrated pocket.  As most fee-mines will only let you use hand
tools, the jackhammers and rock-splitters must be left at home for other excursions. 
Our club’s VP of Programs, Eric Meier, himself presented a a brief pictorial primer on
mining herks, called: “Tool Time at the Rock Club”, you may wish to review.

fullpocket5_f.jpg (53923 bytes) mine10_f.jpg (60582 bytes) mine5_f.jpg (34851 bytes)
A Pocket of Herks! Heavy machinery at work Hard-rock miners at the wall
Photos courtesy of Ted & Anita Smith, The Ace of Diamonds Mine, Middleville, NY   2005

     Whether you stake a claim in the New York karst, or visit the half-dozen or so known
fee-mining sites, you are bound to come away with at least a crystal fragment or two, a
decently-preserved crystal, or maybe you will walk away (with back bent) from your
colossal find of football-sized quartz, dug ceremoniously from the cold, vuggy mud.  Or,
you may silver-pick from the mine stores, various rock shops in the vicinity, rock shows,
or from your local purveyor of Herkimer Diamonds.

Metaphysical Properties

     For those inclined toward healing your tired backs with your crystal finds, you may
elect to prepare you field prize for metaphysical use. 

     Relating to Herkimer Diamonds specifically, “It is claimed that an odd number of
facets on the stone aid in healing, while an even number of  facets create the best
energizers.”  Since ‘herks’ usually occur as doubly-terminated, eighteen-sided crystals,
their best use is as energizers.  To speak of the metaphysical properties attributed to
this stone: “A type of quartz crystal. Cleanses subtle bodies. Reduces stress. 
Balances and purifies energy within body/mind. Similar qualities as clear quartz.
Powerful amplifier. Enhances inner vision. Increases awareness of dreams. Stores
thought forms and information.”[xxii]

     Scientists, philosophers, healers, and even science-fiction fans can attribute some
similar, overlapping property to the energy conduit known as quartz.  We use silicon
wafers to make computer chips, and to craft optical components to better channel light. 
Some sci-fi fans and futurists argue on behalf of emerging silicon-based life forms, and
tout today’s advancing creation of artificial intelligence.  Healers promote this crystal’s
use to channel energy to encourage bodily and spiritual ‘repair’.  And philosophers might
challenge or agree with any and all the above.

     Though this author enjoys a good discussion about rocks and minerals, I find that
just admiring their beauty causes joy, and I forget some of my muscle aches.  So, after
a fashion,it works for me!

Local Quartz

     Most of our club’s collecting area supplies us with some singly-terminated clear
quartz crystals in small dolomite/dolostone vugs associated with white calcite, pink
dolomite, and purple fluorite crystals.  On our recent Binkley-Ober Quarry Field Trip,
we encountered dolomite vugs, some with minute, clear quartz crystals.   However,
this author has no knowledge of any Herkimer-type diamonds occurring in Pennsylvania
or Delaware, though the karst conditions in PA support its existence.   You may wish
to explore the karst in your area.  Perhaps you will make a lucky strike.  If you
remember to work safely and responsibly, you could come away enriched and fulfilled. 
Good luck!


     Some folks like to tumble any broken crystals to achieve beautifully clear, round
gemstones.  Others like to keep nature’s facets intact, albeit incomplete, to mount in
jewelry findings, such as, caged and wire-wrapped pendants, earrings, and rings. 

IMGP4249a.jpg (444690 bytes) necklace2a.jpg (209893 bytes)
Herkimer Diamonds awaiting settings Jewelry Findings
Photo by Ken Casey 2005

     To mount your complete, doubly-terminated specimens is a joy many lucky diamond
hunters find irresistible.  To attribute healing powers to these near-perfect crystals as one
sports them as jewelry is a bonus for those who believe.  This authors loves them in all
forms, and has a project ahead of him to mount some ‘herks’ in caged findings that his
mother-in-law had purchased at the Herkimer Diamond Mine some time ago.  Perhaps
you might enjoy picking up these supplies on your next visit there.

     The countries of Mexico and Italy are producing some nice, faceted quartz these
days.  But, if its not from New York State, it is not a Herkimer Diamond or a Little Falls


Until Next Time

     As there are so many locations to find these cleverly-crafted gems, you may wish to stay a bit
longer to hunt.  If so, you may want to camp at some of these collecting sites.  They offer some
campground/RV Park amenities.  There are a couple of hotels in the area; I will leave the search
for the one most comfortable to your taste.

Be sure to be back by June 1, 2005, though, because we will be packing our parkas for a chilly
tour of Antarctica in search of Fluorite.  See you then!
     Until then, stay safe, and happy collecting. hardhat2a.gif (5709 bytes)      
herkimerdiamond1.jpg (25592 bytes)



Niagara Escarpment

New York State Geological Map
Overview of New York Geology, RPI
The Niagara Escarpment, MSU
Geology and Selected Mineral Deposits, Ontario
Dr. John Grohol’s Psych Central: Niagara Escarpment

Erie Canal

New York History Net: The Erie Canal
The Erie Canal: A Brief History
Erie Canal Museum, Syracuse, New York
Western Erie Canal Heritage Corridor Commission
Erie Canal Online
Erie Canal Park, Camillus, New York
New York History Net: Resource on the Erie Canal
Prehistoric Pittsford and the Erie Canal
Buffalo as an Architectural Museum: Lockport Dolostone
History of the Erie Canal, University of Rochester History Department
Historic Lockport Towpath Trolley
The Erie Canal Game

Herkimer Diamonds

Herkimer Diamonds at
Mineral Gallery at Syracuse University’s ISR
Wild Hogs Adventure Club Herkimer Field Trip
Quartz, University of Waterloo
Herkimer Quartz Crystal Formation



[i]  M. A. McElwee, “Minerals of the Lockport Formation – Brief Article”. May 1999. 30 Apr. 2005

[ii]   “Niagara Falls State Park: Discover the Falls: America’s Oldest State Park”. Delaware North
Companies Parks and Resorts, Inc. 2001.  29 Apr. 2005

[iii]  “Niagara National Heritage Area Study: The Niagara Falls Study”. United States National Park
Service. 20 May 2004. 29 Apr. 2005

[iv]   “Escarpment Centre Ontario – Interpretive Centre for the Niagara Escarpment”. 25 Apr. 2005

[v]  “Get to Know It: The Niagara Escarpment World Biosphere Reserve”. Coalition on the Niagara
Escarpment. 13 Sep. 2004.  28 Apr. 2005

[vi]   “Get to Know It: The Niagara Escarpment”. Coalition on the Niagara Escarpment. 13 Sep. 2004.  28 Apr. 2005

[vii]   “Meet the Commission”. Ontario’s Niagara Escarpment. 7 Jan. 2005.  27 Apr. 2005

[viii]   “About the Niagara Escarpment: Structure & Location”. Ontario’s Niagara Escarpment.
8 Nov. 2004.  27 Apr. 2005

[ix]  “Get to Know It: About the Escarpment: The Geology of the Niagara Escarpment”.
Coalition on the Niagara Escarpment. 13 Sep. 2004.  28 Apr. 2005

[x]“Niagara Escarpment”. 2000-2005. 27 Apr. 2005 

[xi]  “Erie Canal”. Yahoo! Education. 2003.  25 Apr. 2005

[xii]  Ed Nisley. “Dr. Dobb’s Embedded Systems: Only Stone Endures”. 2005. 
24 Apr. 2005

[xiii]   Frank E. Sadowski, Jr. “The Erie Canal: The New York State Canal System”.
2000-2005. [Text from "Unlock the Legend of The New York State Canal System"
Published by The New York State Canal Commission, Albany, NY]. 24 Apr. 2005

[xiv]   “Canal Culture: The Erie Canal: A Brief History”. New York State Official Website.
23 Apr. 2005

[xv]  Julie Daniels; Jane Ladouceur; Tony Mattrazzo. “The New York State Archives
Erie Canal Time Machine: 1918, The Barge Canal”. New York State Archives.  29 Apr. 2005

[xvi]   “Erie Canal: New York’s Gift to the Nation”. New York State Archives. 29 Apr. 2005

[xvii]  Frank E. Sadowski, Jr. “The Erie Canal: Clinton’s Big Ditch”. 2000-2005. 27 Apr. 2005

[xviii]  “Erie Canal”. 2000-2005. 28 Apr. 2005

[xix]   “About the Northeastern Cave Conservancy, Inc.”  29 Apr. 2005

[xx]  “West River Formation, Devonian: Herkimer ‘Diamonds’”. Rensselear Polytechnic Institute,
Department of Earth & Environmental Sciences. 26 Oct. 2004.  27 Apr. 2005

[xxi]  “Virtual Mineral Exhibit: Little Falls Dolostone”. The New York State Museum,
Dr. Marian Lupulescu, Curator of Geology Collections.  26 Apr. 2005

[xxii] Sandie Davis (Star Sensations); Patrick T. Gordon and Myriam Maytorena (Manifest Reality).
“Herkimer Diamond”. 25 Apr. 2005 



Article Contributors

United States Department of the Interior, Bureau of Land Management,
National Park Service  (NPS Photo)


Photo & Graphics Credits

I would like to gratefully acknowledge the generous contributions of our fellow calcite
enthusiasts, collectors, authors, curators, professionals, and club members who made this
work possible. 

Frank E. Sadowski, Jr., The Erie Canal

Ted & Anita Smith, owners of the Ace of Diamonds Mine

Dr. Marian Lupulescu, Curator of Geology, The New York State Museum

Eric Rutnik, The New York State Museum

New York State Department of Environmental Conservation (NYSDEC)

Coalition On the Niagara Escarpment (CONE)

Jasna and Goran Holjak (c/o Niagara Escarpment Commission)

J. Carl Burke, HAER

United States Department of the Interior, Bureau of Land Management,
National Park Service  (NPS Photo)

Niagara Falls State Park, Niagara Falls, New York

2005  All contributions to this article are covered under the copyright protection of this article
and by separate and several copyright protection(s), and are to be used for the sole purposes of
enjoying this scholarly article.  They are used gratefully with express written permission of the
authors, save for generally-accepted scholarly quotes, short in nature, deemed legal to reference
with the appropriate citation and credit.  Reproduction of this article must be obtained by express
written permission of the author, Kenneth B. Casey, for his contributions, authoring, photos, and
graphics.  Use of all other credited materials requires permission of each contributor separately

Links and general contact information are included in the credits above, and throughout this article.
The advice offered herein are only suggestions; it is the reader's charge to use the information
contained herein responsibly.  DMS is not responsible for misuse or accidents caused from this

Suggested Reading


Herkimer Diamonds: A Complete Guide for the Prospector and Collector by Barry S. Moore

by Mossbah M. Kolkas and Gerald M. Friedman

Memphis Archaeological and Geological Society article on Herkimer Diamonds




KEN.JPG (31503 bytes)

   About the Author:  Ken is current webmaster of the Delaware Mineralogical Society.  He has a diploma in Jewelry Repair, Fabrication & Stonesetting from the Bowman Technical School, Lancaster, PA, and worked as jeweler.  He has also studied geology at the University of Delaware.  And, he is currently a member of the Delaware Mineralogical Society and the Franklin-Ogdensburg Mineralogical Society.  E-mail:


McElwee, M. A. “Minerals of the Lockport Formation – Brief Article”. May 1999. 30 Apr. 2005

“Niagara Falls State Park: Discover the Falls: America’s Oldest State Park”. Delaware North
Companies Parks and Resorts, Inc. 2001.  29 Apr. 2005

“Niagara National Heritage Area Study: The Niagara Falls Study”. United States National Park
Service. 20 May 2004. 29 Apr. 2005

“Escarpment Centre Ontario – Interpretive Centre for the Niagara Escarpment”. 25 Apr. 2005

“Get to Know It: The Niagara Escarpment World Biosphere Reserve”. Coalition on the Niagara
Escarpment. 13 Sep. 2004.  28 Apr. 2005

“Get to Know It: The Niagara Escarpment”. Coalition on the Niagara Escarpment. 13 Sep. 2004. 
28 Apr. 2005

“Meet the Commission”. Ontario’s Niagara Escarpment. 7 Jan. 2005.  27 Apr. 2005

“About the Niagara Escarpment: Structure & Location”. Ontario’s Niagara Escarpment.
8 Nov. 2004.  27 Apr. 2005

“Get to Know It: About the Escarpment: The Geology of the Niagara Escarpment”.
Coalition on the Niagara Escarpment. 13 Sep. 2004.  28 Apr. 2005

“Niagara Escarpment”. 2000-2005. 27 Apr. 2005

“Erie Canal”. Yahoo! Education. 2003.  25 Apr. 2005

Nisley, Ed. “Dr. Dobb’s Embedded Systems: Only Stone Endures”. 2005.  24 Apr. 2005

Sadowski, Jr., Frank E. “The Erie Canal: The New York State Canal System”.
2000-2005. [Text from "Unlock the Legend of The New York State Canal System"
Published by The New York State Canal Commission, Albany, NY]. 24 Apr. 2005

“Canal Culture:The Erie Canal: A Brief History”. New York State Official Website.
23 Apr. 2005

Daniels, Julie; Ladouceur, Jane; Mattrazzo, Tony. “The New York State Archives
Erie Canal Time Machine: 1918, The Barge Canal”. New York State Archives. 
29 Apr. 2005

“Erie Canal: New York’s Gift to the Nation”. New York State Archives. 29 Apr. 2005

Sadowski, Jr., Frank E. “The Erie Canal: Clinton’s Big Ditch”. 2000-2005. 27 Apr. 2005

“Erie Canal”. 2000-2005. 28 Apr. 2005

“About the Northeastern Cave Conservancy, Inc.”  29 Apr. 2005

“West River Formation, Devonian: Herkimer ‘Diamonds’”. Rensselear Polytechnic
Institute, Department of Earth & Environmental Sciences. 26 Oct. 2004.  27 Apr. 2005

“Virtual Mineral Exhibit: Little Falls Dolostone”. The New York State Museum,
Dr. Marian Lupulescu, Curator of Geology Collections.  26 Apr. 2005

Davis, Sandie (Star Sensations); Gordon, Patrick T. and Maytorena, Myriam (Manifest Reality).
“Herkimer Diamond”. 25 Apr. 2005


Invitation to Members


Want to see your name in print?  Want to co-author, contribute, or author a whole Mineral of the Month article?  Well, this the forum for you!

And Members, if you have pictures, or a story you would like to share, please feel free to offer.  We'd like to post them for our mutual enjoyment.   Of course, you get full photo and author credit, and a chance to reach other collectors, hobbyists, and scientists.  We only ask that you check your facts, give credit where it is due, keep it wholesome for our Junior Members watching, and keep on topic regarding rockhounding.

You don't even have to be experienced in making a webpage.  We can work together to publish your story.  A handwritten short story with a Polaroid will do.  If you do fancier, a text document with a digital photo will suit, as well.   Sharing is the groundwork from which we can get your story out there.

Our club's webpages can reach any person surfing the net in the world, and even on the International Space Station, if they have a mind to view our website!

We are hoping for a possible tie-in to other informative programs upon which our fellow members might want to collaborate.  Contact any officer or board member with your suggestions.

June''s MOTM will be "Antarctic Fluorite".  For July 2005, we are waiting for your suggestions.  What mineral do you want to know more about?

aniagate.gif (1920 bytes)


Most of the Mineral of the Month selections have come from most recent club fieldtrips and March Show Themes, thus far.  If you have a suggestion for a future Mineral of the Month, please e-mail me at:, or tell me at our next meeting.






Next Meeting

April Program, Monday, April 8, 2013:

"Destruction of the Fossil Exposures in the Chesapeake Bay Area" presented by Dr. Lauck Ward

General Club Meeting:
April 8, 2013

We are meeting at
Greenbank Mill

Special Meetings:

*Show Committee Meeting, April or May, 2013

*New Home/Lapidary Committee, 2013

*Board Meeting,  April, 2013

Next Field Trips


Past Fieldtrips

Next Show
DMS March Show
March 1-2, 2014 at DelTech Stanton


Our 2013 Show Theme was:
"All That Glitters is as Good as Gold!"

March Show 2013 Report






Fossil Forum

"Dinny, the Dino"

"Belemnites are coming"


MOTM June also commemorates our 50th Show!

It's shiny, yellow, and is a symbol of 50 Years!Can you guess?


Collecting Adventure Stories:

"Sunny Brook Crick Goethite" by Joe Dunleavy