Happy New Year, ye
students of geology! This January, our
us rolling about into the subject of gravel and pebbles of the First
State. Second in this two-part
series on Delaware Quartz, we'll visit a gravel quarry, pebbles
downstate, Paleo-Indian artifacts,
and various other products of erosion. Yes, we get to traverse and
stop in New Castle, Kent,
and Sussex Counties to find rounded quartzes upon
which to gaze.
We are in mid-winter, yet our January thaw has given us a splendid
opportunity to search
outdoors. It's a bright and sunny day, so
part 1, we covered igneous quartz and bedrock,
and touched upon our beach sands. This
month, we will study the sands and pebbles of time that lie around
Delaware’s coast, rivers,
creeks, and aquifers. In other words, sedimentary quartz.
Erosion by wind and water has deposited
grains of quartz sand from microscopic to larger
pebbles here. Though glaciations did not officially touch Delaware
erosion of glacial material left to the north of us, from Pennsylvania
and New Jersey, did arrive
here eons ago.
Work by geologists gives us an overview as
to the surficial occurrences of tumbled quartzes.
And, digs by both archaeologists and gravel miners point to areas rich
in rounded silicon dioxide,
which can help us to paint a picture of the widespread availability of
this mineral to view and to
As quartz was geologically created in a
range of colors, whose original occurrences span the
greater northeastern United States and Canada, the area of colorful
material which have aggregated
over Delaware’s ancient landmass is vast. So, that means that we can
find colors ranging from clear,
white, yellow, pink, purple, and green strewn across our local
Though most terrigenous erosional detritus
is from places outside of Delaware, these mineral
morsels do belong here by virtue of having arrived under our feet
thousands of years before native
Delawareans came here. Since they are ours to collect (with appropriate
permissions, of course),
we can assemble a vast array of colorful specimens to show and to share!
So come on along, we have another Delaware
Quartz fieldtrip to make.
We can, however, take our pick of geology
hikes to view them in situ. Or, as the Delaware
Geological Survey has organized itineraries for us, called
We''ll share a bit
from the Survey's suggestions, coupled with our club's and this author's
Our article will take us across marshy,
gravelly, and beachy landscapes.
people in general seem to admire are colorful pebbles. Whether
they are polished
or rough, the natural form seems to lend itself to appreciation by an
area of the human psyche
processes beauty. Streamworn river rocks and pebbles do foot the
From parkland boulders to
river, creek, and ocean shore rounded stones, Delaware's varieties
have inspired art, collecting, and articles about our native wonders.
Our three counties have
landscapes for us to set feet and eyes upon. Please do join us!
|Quartz Pebbles on Brandywine
Creek bank, Wilmington, Delaware (Photo by Ken Casey)
We covered the etymology of
Part 1. We'll focus now on the pebbled form.
"A pebble is a
rock with a
particle size of 4
phi scale of
rock made predominantly of pebbles is termed a
It is a small stone, especially one worn smooth by erosion.
The word "pebble" derives from the
Middle English pobble, pibel, and pebul. Back from
there, the Old English papol-, as in papolstān (pebblestone).
Today we pronounce it "pĕb'əl".
In October of
last year, we covered some chemistry and physics of Delaware's quartz.
silicate of chemical formula
And, on the
Moh’s Hardness Scale, it
Since we have those concepts under our belt, we will concentrate on some
of the geological
processes that create our rounded quartz rocks. Also, we'll touch
upon aspects of hydrology
and sedimentology. We will visit these disciplines below in our
Some Delaware Quartz Geology
start our excursion this month with a leap into the prehistoric past.
From the quartzes
of Earth's beginning to siliceous fossils to early
native artifacts, Delaware Quartz has formed
and reformed into evidence
which helps us to understand our past.
Most are not found in rounded pebble form,
since these items are rarely the products of
alluvial flow, though, they are quartzes of life, and relate to our
modern cultural use of pebbles.
The first item is plant
fossils that we would encounter on a
dig near Odessa, would show us in
their preserved wood grain their
origins as earlier trees.
Wood from Odessa, Delaware (Photo by Ken Casey)
The first hand-hewn quartz artifacts we could
an archaeological dig would be
Delaware Paleo-Indian arrowheads and spearheads used for hunting.
I understand many of the
items found were knapped from Jasper. "The
nomadic hunters of this Paleo Indian period were
among the most skilled makers of stone tools
in the world. They would travel great distances to
quarry the best flinty stones from which they made
exquisite spearpoints, knives, and small tools.
Archaeological evidence suggests that they traveled
to Piedmont quarry sites near the project
occasional resupply. Archaeologists in the
Delmarva Peninsula have been very interested
establishing the locations of stone raw material
quarry sites and the mechanisms by which
materials were obtained and reached the locations
where we now find them."
artifacts found near Christiana, DE
on display at the DGS
||Close-up of arrowheads from
on display at DGS
|(Images taken with
permission of the Delaware Geological Survey/ Photos by Ken
A variety of Delaware Paleo-Indian
Bifurcate Projectile Points
(Courtesy of the Delaware Archaeological
Museum, Dover, Delaware)
Though I have never
found any such tools, I am told that they have been discovered at
Pond State Park.
Since this is a public park, no collecting is allowed here.
can visit our friends at the Iron Hill Museum in Newark or the
Our virtual hike itinerary will have us start on
the Delaware River shore at
Fox Point State
Park. Not many pebbles here, but it is a landmark view of the
river. It is also the start of the
longest trail Delaware Coastal Heritage Greenway:
The Pinelands Trail. Since it's a nice day,
we'll walk down to Newark (though a bit off of the main trail) to a
favorite local repository of
history, the Iron Hill Museum. How about a tour of some Native
After that, we'll resume our corridor jaunt to
Odessa and onto Cape Henlopen and Lewes,
where we will stop at the
Zwaanendael Museum to learn more about the
earliest settlers' lives.
Feel free to take in fresh air and photos of our precious wildlife.
And, we might find a few
quartz pebbles along the way--the mainstay of Delaware collectible
Let's stretch our attention back further to before the
first European settlers arrived, say
Informational sign about
Shipwreck at Lewes Beach
(Photo courtesy of the
State of Delaware)
Some evidence of history that we might encounter nearby on the beach might be an arrowhead, or
even a 300-year old relic of an antique sailing ship. There is a
sign posted at Lewes Beach
informing us as to the disposition of any finds we might make there. The Zwaanendael is
greatly interested in recovering and interpreting our local history. So, if we come across
anything, we'll walk over to the
curator's office and hand it over for posterity.
500 years, or so, ago to the Lene Lenapé people and their earlier
This native Delawarean people pass on to us
both an oral tradition about the first rocks in
Delaware and a belief about certain local quartz.
From crafting arrowheads and eking a life
around sand to adding
silica into their clay pots, the Delaware Indians, or Lenni Lenapé
People, also passed their creation story as part of the people’s oral
Lenapé Creation Story (Lenapé Kishelamàwa'kàn),
the existence of all rocks, including
Delaware quartz, was attributed to
one of four powerful Spirit Beings sent by Kishelamàkânk,
the Creator. Here is part of
“There were first created the Keepers of Creation, four powerful
Spirit Beings, to help him
in his task of fulfilling and creating the
vision: the Spirits of the Rock, Fire, Wind, and Water.
Into each he
breathed life and Spirit, giving each different characteristics and
four beings were: Muxumsa Lowànewànk, our Grandfather in the North. He was placed there
to control the power of rock. He gave forth solidity and physical form
to the Creator's thoughts,
to his vision. North Grandfather gives us the
wintertime, ice, snow, and cold; also, our bodies,
the rocks, the trees,
and all that we see around us;”
Some of these rocks were pure, clear quartzes. Pieces of broken
veins and crystals from
the upper Delaware River basin did erode out over time, and found their
way to be naturally
deposited upon the banks of the Delaware River and Bay. Along the
way, each fragment was
worn by water action and polished by rubbing against the other pieces in
the stream currents.
mile journey that takes thousands of years to complete. The strong tidal
against the hulk of the sunken concrete ship "Atlantus" is the cause for them to wash ashore
great abundance.” The people believed that each stone
power bringing success and good fortune" for the one who holds it.
They gave them as gifts
or traded them with early European Settlers. These
Cape May Diamonds
are one of our local
|Lewes Beach sand and pebbles
(Photo by and courtesy of Mike Mahaffie)
As logic might suggest, the Delaware Bay
shore in southern Delaware lays claim to its
own cache of fine quartz pebbles. Some are found at Lewes Beach.
Do they have a fancy
name, such as "Lewes Diamonds" from the
Diamond State, I do not know.
Perhaps we could dream up a new name.
"This particular stone is often described as
having a harmonization
effect. Dreams of it may reflect a desire for or acquisition of harmony
with the world."
“Daily Dream Decoder: Quartz”)
Other cultural beliefs include pebbles,
which are mostly quartz. "A custom among Jews
is to leave a small stone behind when they visit
the grave of a loved one, a token of remembrance.
Thus even the most
common thing, a pebble from the ground, can be invested with human
Cairns are another example.
This conical pile of stones served as a site marker or landmark,
usually for remembrance or navigation. At the famous
site of American
Henri David Thoreau, thoughtful folks who
visit may place a pebble from the surrounding
onto an existing
pile of remembrance rocks. My wife and I visited there some years
our respects, as such. Pebbles as a positive symbol can be a good
thing--either left or
I mentioned the sciences of hydrology and sedimentology. These are
the two main
sciences by which one might study Delaware's stream deposits,
erosion, and coastal
As our gravel and sand deposits
are essentially alluvial in nature, there isn't a lot more to
discover within the scope of our trip than how we can learn more beyond
the beauty of our
pebbles. For fun, we'll search out gravels in the next section.
So, let's pull up a rock and sit
a spell. We'll discuss these two "-ologies" to give us a
basis for future studies.
"Hydrology (from Greek: Yδωρ, hudōr,
"water"; and λόγος, logos, "study") is the study of
distribution, and quality of
throughout the Earth, and thus addresses both
hydrologic cycle and
water resources. A practitioner of hydrology is a hydrologist,
within the fields of either
physical geography or
Subdomains of this field link it to meteorology and geology.
|Marine life abounds at Lewes
(Photo by and courtesy of Mike Mahaffie)
Water is central to this
discipline. Hydrological research underwrites our study of ancient
water movement, and subsequent deposition of sediments, and the study of
"[t]he scientific study of
the properties, distribution, and effects of water on the earth's
in the soil and underlying rocks, and in the atmosphere."
Environmental Hydrology, for
example, can concern us with geospatial
waterflow events which affect our lives. Since water covers about 70% of the Earth's surface,
and is necessary for much of life on this planet, it's study is of
paramount importance to our
(Source: NOAA's NWS
Office of Hydrologic Development)
very powerful forces, one of which is the movement of water.
storm surges and runoff are but
three classical aspects of this volumetric transfer.
ancient times, both liquid and solid water have
shaped and carved our landscapes.
pebbles are a product of
these erosional processes--our focus here.
Run emptying into Brandywine Creek at BCSP
(Photo by Ken Casey)
Today, we can study the creation and movement of
pebbles through these sciences of
hydrology and sedimentology. Modern scientists and civil engineers
attempt to halt the
destructive effect of these processes from causing havoc with our
how these processes work on all scales. By observation
trending the results, preventive and emergency solutions may
be found. Items, such as
events, tailwater, hydraulics, and culvert calculations,
can be quantified, then applied to land management. Moreover, these
can be applied to ancient geology
of our Delaware.
Through advances in
computer-modeling, we can can make better maps to understand the
basic lithostratigraphy (or geologic rock and sediment layering).
Let's look underground.
|Bethany Beach (Photo by Brooks
Layton/ Courtesy of Sussex County, Delaware Government)
Below today's Delaware estuaries
lie evidence of more geologically ancient coastal water
environments. Over the eons, the landmass, which became The First
State, was covered fully
or partially by water, eroded, and built up again by sedimentary
processes, among others.
The concepts underlying hydrology
and sedimentology overlap into our study of Delaware
pebbles--and our largest mined resources: sand and gravel. Put on
your hardhat; we are
about to enter a quarry!
Society for Sedimentary
Association of Sedimentologists
siliciclastic sedimentary rocks
Hydrology Resource Center
American Institute of Hydrology
The International Association for
Department of Hydrology and Water Resources: University of Arizona
Delaware, Pennsylvania & New Jersey Geological Maps
Yes, right in our own backyard
are numerous gravel quarries--in all three counties.
it all get there? Well, our coast has been
geologically active almost continually, since its landmass
area was created. As a
coastal deposition zone on the
trailing edge of the North American
continent, sediments have formed, been lain down, and
metamorphosed over and over again.
As sea levels have dropped greatly over ice
ages and geologic time, exposed rock weathered. "Later, the sea again covered most of
Delaware and deposited Chesapeake Group (Miocene age).
consists of interbedded silts and sands and reaches a thickness of 400
feet at the
St. Jones. Many of the sandy layers contain important supplies of water for municipal and
industrial use in the Dover area.
The repeated advance and retreat of continental glaciers during
one to two million years (Pleistocene age) caused dramatic changes in
relative sea level
and the configuration of streams draining from the
glaciers. The deposits from meltwater runoff
supplies most of the sands and gravel for construction. Sand and gravel are the most important
mineral resources in Delaware with the most potential source for Kent
County being in and around
the St. Jones River Component area."
(Above, left): Close-up of Upper Delaware
River gravel from near Riverton, New Jersey
(Below, left): Eroded gravel bank of Upper
Delaware River near Riverton, New Jersey
As gravel is present in many surface deposits in The First State, a
valuable resource is available
to us without hard rock mining. Any of us might be the beneficiary
of gravel in our local construction.
Perhaps some of the trails we have traversed this trip are underlain
with Delaware's finest gravels!
|Major Sand and Gravel
Operations Map for Delaware, June 2004
(Courtesy of the Delaware Geological Survey)
The Pleistocene Columbia Formation holds most of the sand and
gravel mined in the First State
as road and construction aggregate.
Of course, economically sized gravel may be found
all along the course of the modern Delaware
River, from New York State, past Pennsylvania and New Jersey at the
Delaware Water Gap, and
all down Delaware and New Jersey's shared borders and bay.
|Yes, you too can
own a Delaware River Gravel Quarry. This one is currently
up for sale in Hancock, NY.
Upper Delaware Real Estate)
According to Kelvin W. Ramsey, Geologist for the
Delaware Geological Survey, in a
delivered at the
GSA event in 2001, "Deposition
of inner Coastal Plain stratigraphic units was
essentially complete by the late Pliocene. This interval was
characterized by high sediment supply
driven by climate change and establishment of present drainage systems.
This resulted in
widespread deposition of the Beaverdam Fm. in Delaware..." as sediments
were redistributed all
over the Delmarva peninsula. Quaternary era sea-level rising also
contributed to resedimentation.
These are some of the events that have resulted in the beach gravel
deposits we mine today.
|Bethany Beachfront, home of
wildlife and sediments
(Photo by Brooks Layton/Courtesy of Sussex County, Delaware
We have so much sediment available that, "Delaware is the only state in the union that does
View down large boulder upon a gravel
bed bank of the Brandywine Creek, Wilmington, Delaware
(Photo by Ken Casey)
Before we proceed, let's define what gravel
is. Gravel pebbles are naturally eroded rocks,
larger than sand, and smaller than cobbles. Geologically defined,
its dimensions range from
2 mm-75 mm (1/12"-3"). These sedimentary particles will pass through a
3" sieve and retained
by a No. 4 US Standard sieve (3/16"). Anything larger than 2mm is called gravel. One standard
construction materials definition lists gravel as a mix of sand,
pebbles, and small cobbles from
2 mm-200mm in diameter range. Delaware's quarries host material on
the smaller (and more
practical size), that is, less processing for immediate distribution and
Gravel boards at realdo.com)
There are eleven majors sand and gravel
operations in our state today. Surface quarries
span all three counties. The closest to our clubhouse is on Route
9, just south of the town of
New Castle. I remember another now defunct quarry that we called
"the sandpits". It stretched
about two miles by one mile, and was bordered by Interstate 295, Routes
13/40 to the north
and west, and by the housing
developments of Swanwyck Estates, Castle
Hills, and Jefferson
Farms to the east and south.
The angular, orange sand was good for
construction. The site has since been reclaimed in
the 1970s as Southgate Industrial Park. There was even a small urban legend that
the larger puddles there; and, that they were so hungry,
that you could put anything on a fish
hook, and they would bite.
As finding these deposits are still hit and miss,
due to the nature changing
geology, DGS's maps, reports, and services for the
citizens, local governments, and businesses
go a long way to the support
of interests in our state.
Fortunately for us, our search for smaller
quantities of Delaware's colorful pebbles, is a lot
Pebbles of quartz may be found almost anywhere in the First State.
We will visit the First
Lewes, Delaware to find some. Then, we will venture across the
choppy waters of the
to a New Jersey beach, which has comparable pebbles: Sunset Beach on
||Shallow waves ripple around a
wave-battered scallop shell at Lewes Beach
|(Photos by and
courtesy of Mike Mahaffie)
Delaware Greenways Project expands, we’ll be able to hike directly
to other geologic
locations rather efficiently on current and future MOTM fieldtrips.
Thanks to the State of Delaware
and its partners, our educational and recreational experiences will be
enhanced. We can now
almost walk through all three counties via the East Coast Greenway!
It might take us maybe five
or six days to traverse the over 100-miles of topography, but we're in
shape for virtual jaunt, eh?
Now, we'll say farewell to our tour guide at
Zwaanendael Museum, and hit the beaches!
Next, we are onto Lewes Beach to
comb for some gemmy rounded quartz--maybe these
are the "Lewes Diamonds" that we dreamed up earlier?! Or, even the
"Lewes Dutch Diamonds",
now that we've been inspired by the history at the museum. Put on
your sunglasses, and
let's scour the sands for some waterclear pebbles!
If you're up to it, we can take a side trip to both
Fowlers Beach and
Slaughter Beach, both
which boast fine and colorful pebbles of note.
Mark Marquisee has
made his interest in our
local gems by photographing them for over twenty years now. You
can even purchase one of
his posters, if you like. You might see him at the next Coast Day 2008.
(Left): Colorful beach pebbles, including
clear quartz, Lewes Beach, Delaware (Photo by and courtesy
of Mike Mahaffie)
Hope you filled your bags with some local
treasure. We are now off from Lewis on a nautical
excursion over the Delaware Bay to the shore of
Cape May, New Jersey.
Come on, I know you
want to sing it, "One the way to Cape May...".
|We're embarking for Cape May,
New Jersey on the Cape May-Lewes Ferry
(Photo by Brooks Layton/Courtesy of Sussex County, Delaware
Silliness aside, let's buy our tickets and board
the Cape May-Lewes Ferry. The club will
treat to lunch on board. If you're prone to seasickness, rest
easy, and to your remedies, if
you have them. When we're settled, we can inspect our Lewes finds
in preparation to compare
them to the Cape May variety.
Both sides of the bay seem to produce similar pebbles,
with one difference, Jersey folks
have kept a native legend alive about the appreciation of their shore's
pebbles. I think a bit of
modern marketing helps, too.
Ah, after our 17-mile voyage,
we're here! Let's mount up and disembark the ferry
boat, then onto the beach. We'll hike about three
miles or so through the wildlife management area, and along the
shoreline, until we reach our
last destination this trip:
It's a small stretch of beach, nestled near the
tip of the cape on the bayside. Yet, it has
a charm of bygone days. Two modest one-story beach-type buildings
house a gift shop, the Sunset Beach Gift Shop, to be exact.
Our hosts encourage us to collect a
modest quantity of
Cape May Diamonds for our personal
use. Let's fill up, then visit their shop. Inside we will
find machine-tumbled and highly-polished
quartz diamonds to peruse or purchase. Yes, they have even brought out their beauty further by
setting these stones in jewelry--a nice souvenir. Of course, we
can buy and mail a post card
there to our friends who could not make this journey with us today.
(Above, left): Sunset Beach sign at Cape May
(Below, left): Our entrance to the Sunset Beach Gift Shop:
The person to the left is DMS Member Eileen Casey, my lovely
wife. (Photos by Ken Casey)
After getting an idea what Cape May Diamonds can look at their best,
let's comb the beach
a little more in search of the nicest pebbles for our collection.
tumbling for 3-weeks, these Cape May Diamonds shine brightly
(Photo by Ken Casey)
Our view will include fellow beachcombers, boaters,
and the derelict concrete ship "Atlantus",
which went aground in a storm in June 1926. It serves as landmark
and a marine habitat for us.
Beach looking north
rolls on some Cape May Diamonds
||Close-up of Cape May Diamonds
Jetee, Atlantus, Boat
intrepid author (a rare photo)
||S. S. Atlantus beach
|(Photos by Ken
Lapidary tumbling can enhance that of nature's,
so I fulfilled a promise to my wife to make
for her a box of Cape May Diamonds. I collected them on our
vacation, recently after we were
married, and for three weeks finished them in a toy rock tumbler--the
kind you can get for about
$10.-$20. She loved them, and keeps them on her dresser.
Oh well, it's time
to start back to the clubhouse, when I start telling
stories. So, grab your bagful of pebbles, and let's go home!
(Left): Wooden box filled with tumbled and polished Cape May
Diamonds (Photo by Ken Casey)
Delaware Bay Links
Sunset Beach Gift Shop
Beach, New Jersey
Cape Henlopen State
Lewes: The First Town in the First State
The Lewes Historical Society
Mark Marquisee pebble photographer Slaughter Beach
Please join us at our two museums of note this
month. We are visiting--you guessed it--the
Zwaanendael Musem in Lewes, Delaware and the Delaware Archaeological
Museum in our
State Capital City of Dover, Delaware. Both official Delaware
Museums, each offers a unique
experience at discovering early life in the state. A bit of
geology can be found here and there,
Zwaanendael Museum offers exhibit that cover the rich maritime
history of the area, as
well as coverage of 11,000 years of prehistory, which includes Paleo-Indians.
A current exhibit,
Through Recovery" offers us a glimpse into shipping of the 1760s
from the Roosevelt Inlet Shipwreck. Amazing what has happened
around our pebbles over the
Our second museum is the
Delaware Archeological Museum in Dover. This museum hosts
a greater scope in Delaware's long history, as it contains artifacts
from the entire state. Items
such as arrowheads, stone and bone tools, and ceramics are showcased.
In May each year,
the museum hosts a series of events aligned with
Days and Delaware
As Delaware quartz occurs in commercial quantities
as gravel and sand, these easily accessible
forms are readily used in construction and landscaping. Our large
stretches of bay and ocean
beaches are for recreation, and as nature preserves.
|Delaware Bay quartz pebbles
(Photo by Ken Casey)
DelDOT's Cultural Resources
Here is where DMS Members
can add their Delaware Quartz photos to share with us.
Until Next Time
We hope you have enjoyed our historic visit to
Delaware Quartz. Please join
us next month, for another article, and we shall journey together!
Until then, stay
safe, and happy collecting.
would like to gratefully acknowledge the generous contributions of our
Quartz enthusiasts, collectors, authors, curators, professionals, and
club members who
made this work possible.
Nenad Spoljaric and Robert Jordan, Thomas E. Pickett,
Delaware Geological Survey
©2008 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
article. All opinions, theories, proofs, and views expressed within this
article, and in others on this
website, do not necessarily reflect the views of the Delaware
Delaware Piedmont Geology including a guide to the rocks of
Red Clay Valley
by Margaret O. Plank and William S. Schenck
Gem Trails of Pennsylvania and New
Jersey by Scott Stepanski and Karenne Snow
About the Author:
Ken is current webmaster of the Delaware
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
And, he is currently a member of the Delaware
Mineralogical Society and the Franklin-Ogdensburg
Mineralogical Society. E-mail: