John Bryant Paine III on wed 8 sep 04
Hi everyone. I have to admit to being more of a mineralogist than a
ceramist. One of the departments of my mineral collection is heavy sands,
collected from marine and lacustrine environments around the world, but
mostly from the USA. On the beach, heavy minerals are concentrated by wave
action: as the wave recedes down the slope, it drags grains of sands with
it. The grains that are dragged downslope the farthest are the grains of
the lowest density (specific gravity), typically being quartz (D = 2.65).
The heavies, which can have D greater than 4, tend to remain behind. Thus,
the best accumulations of heavies are found above the mean high water mark,
having been left that high during storms. (Ironically, many beach goers
think that these heavies are "pollution", such as from an oil slick!) Not
all beaches come equally well-endowed. In Florida, I only saw traces, of
very fine-grained material, mostly ilmenite (the iron titanium oxide you
have all heard of) and/or use). Also present were colorless grains of a
mineral that fluoresces yellow-orange, best under short-wave UV: this
happens to be zircon, your familiar opacifier. The fluorescence is due to
trace content of certain rare earths such as terbium and dysprosium. I
never saw the part of Florida where inland beach accumulations are actually
mined for zircon and ilmenite, but I have acquired samples of their product,
which probably includes some of the zircon and ilmenite in (ceramic)
commerce. The Outer Banks of North Carolina have some areas where the
accumulations of ilmenite and garnet are several inches thick, and nearly
quartz-free. Coquina Beach near Manteo is the best spot I have found so
far. Some heavies turned up along the river bank near the Post Office in
Yorktown, Virginia. I have not visited any of the beaches between VA and
NY, so have no info on these. Long Island is a terminal moraine from the
last glaciation, and its sand, along with that on Cape Cod and the Islands
is quite coarse. These sands are geologically young, so that the magnetite
has not had time to oxidize and degrade, so that magnetite, not ilmenite, is
the dominant black in these. I collected quarts of coarse dark purple
garnet-magnetite sand more than 30 years ago, waiting for our turn to board
the ferry at Orient Point, Long Island. This sand was above the mean high
water mark immediately north of the ferry. Inland, in the Adirondacks, a
small beach at Hearthstone Point campground on Lake George had essentially
quartz-free purple garnet-magnetite-ilmenite sand (as of 1968). I have also
collected heaviest from Cape Cod and the Islands, including such places as
Naushon Island, Chappaquiddick, the beaches north of Chatham, etc. I even
managed to find heavies at what had been the family beach at Prides
Crossing, Beverly, Massachusetts. I collected magnetite in an abandoned
gold stream near Greenough, Montana. The nudist beach (whose name I have
forgotten; not Wreck Beach) on the south side of Vancouver harbor, below the
UBC campus, also has abundant heavies.
I have never collected the Great Lakes. The famous black sand of Kalapana,
Hawaii, is basalt rock. The Hawaiian green sands are olivine, which might
make an interesting glaze ingredient. Those of you local to the areas I
have mentioned: go out and enjoy! Best regards, John B. Paine III,
jbp3@comcast.net, Midlothian, Virginia
John Rodgers on wed 8 sep 04
Hi John,
I found your discussion of your collections to be fascinating. Though
not that deep into mineralogy myself, I have always had an awareness of
the mineral and geological composition of our world. A few of the things
in the area I live in now are convoluted layers of rock that are exposed
in cuts where highways are put through. One can drive in certain areas
in the greater Birmingham area and see bands of coal, layers of clay
with different mineral stains, cuts through layers of limestone exposing
ancient fossilized creatures, all very interesting to me.
In Alaska there were many interesting deposits. Particularly along shore
lines. In the Kenai area the beaches contained contained soft coal. The
deposits would stick up through the sands on the beach, and some
citizens would gather the coal for heating fuel in the winter. There
were also some semi precious stones found on those same beaches, though
I was not that familiar with them. Thee was a place where in the summer
I would go and pick up dried chunks of a grey clay, that was virtually
free of any debris, particularly sand. I would gather it and use in my
clay art work.
I lived on Kodiak Island for a time, and there was a beach there where
one could, if you really worked at it, pan for gold in the black sands
on that beach and get a little color. The Alaska Range of mountains is
still volcanically active, and there are many mineral deposits to be
found related to volcanic activity. I have collected ash from the
eruptions of Mt. Illiamna, Mt. Augustine, Mt. Redoubt, and Mt. Spurr.
The latter three of which dumped ash on my house when I lived here along
Cook Inlet. The ash from Redoubt and Spurr when used in my glaze gave me
a rather non-descript mottled pea green, while the ash from Augustine
gave a glaze with beautiful light and dark pink streaks through it.
In Nome, up by Norton Sound on the Western side of the state, even to
this day, people occasionally work the old gold beaches of Nome using
portable dredges. Once can still find enough gold to MAYBE pay for ones
daily expenses. Interestingly, further out and underwater, there are
found nodes of platinum.
For myself, the clay deposits were most interesting. and the gray clays
I collected would fire to a strong rust red. I used it principally to
produce what was known as "Alaska Clay" - which really was a marbled mix
- when fired - of white and red earthenware with a clear glaze over it.
It's popularity rises and falls. This same clay mix is found variously
in other states. Here that same red and white clay mix is known as
"Alabama Clay". It's appearance is really the result of "Technique"
rather than it being any special kind of clay.
One final remark - Alabama in certain areas is blessed with quartzite
rocks which are basically oxides of silicon. There is so much present
that it is economical to mine it and ship it to processing plants here
to produce refined silicon. The quartzite rocks are layered in with
layers of coke, all in electric ovens. At temperature the carbon in the
coke combines with the oxygen in the quartzite and goes up the chimney
as carbon dioxide gas, and the liquid remaining in the bottom of the
furnace runs out into molds to form grey, non-descript ingots of near
pure silicon, which gets shipped to the industrial and manufacturing
centers of America.
Regards,
John Rodgers
Chelsea, AL
John Bryant Paine III wrote:
>Hi everyone. I have to admit to being more of a mineralogist than a
>ceramist. One of the departments of my mineral collection is heavy sands,
>collected from marine and lacustrine environments around the world, but
>mostly from the USA. On the beach, heavy minerals are concentrated by wave
>action: as the wave recedes down the slope, it drags grains of sands with
>it. The grains that are dragged downslope the farthest are the grains of
>the lowest density (specific gravity), typically being quartz (D = 2.65).
>The heavies, which can have D greater than 4, tend to remain behind. Thus,
>the best accumulations of heavies are found above the mean high water mark,
>having been left that high during storms. (Ironically, many beach goers
>think that these heavies are "pollution", such as from an oil slick!) Not
>all beaches come equally well-endowed. In Florida, I only saw traces, of
>very fine-grained material, mostly ilmenite (the iron titanium oxide you
>have all heard of) and/or use). Also present were colorless grains of a
>mineral that fluoresces yellow-orange, best under short-wave UV: this
>happens to be zircon, your familiar opacifier. The fluorescence is due to
>trace content of certain rare earths such as terbium and dysprosium. I
>never saw the part of Florida where inland beach accumulations are actually
>mined for zircon and ilmenite, but I have acquired samples of their product,
>which probably includes some of the zircon and ilmenite in (ceramic)
>commerce. The Outer Banks of North Carolina have some areas where the
>accumulations of ilmenite and garnet are several inches thick, and nearly
>quartz-free. Coquina Beach near Manteo is the best spot I have found so
>far. Some heavies turned up along the river bank near the Post Office in
>Yorktown, Virginia. I have not visited any of the beaches between VA and
>NY, so have no info on these. Long Island is a terminal moraine from the
>last glaciation, and its sand, along with that on Cape Cod and the Islands
>is quite coarse. These sands are geologically young, so that the magnetite
>has not had time to oxidize and degrade, so that magnetite, not ilmenite, is
>the dominant black in these. I collected quarts of coarse dark purple
>garnet-magnetite sand more than 30 years ago, waiting for our turn to board
>the ferry at Orient Point, Long Island. This sand was above the mean high
>water mark immediately north of the ferry. Inland, in the Adirondacks, a
>small beach at Hearthstone Point campground on Lake George had essentially
>quartz-free purple garnet-magnetite-ilmenite sand (as of 1968). I have also
>collected heaviest from Cape Cod and the Islands, including such places as
>Naushon Island, Chappaquiddick, the beaches north of Chatham, etc. I even
>managed to find heavies at what had been the family beach at Prides
>Crossing, Beverly, Massachusetts. I collected magnetite in an abandoned
>gold stream near Greenough, Montana. The nudist beach (whose name I have
>forgotten; not Wreck Beach) on the south side of Vancouver harbor, below the
>UBC campus, also has abundant heavies.
>
>I have never collected the Great Lakes. The famous black sand of Kalapana,
>Hawaii, is basalt rock. The Hawaiian green sands are olivine, which might
>make an interesting glaze ingredient. Those of you local to the areas I
>have mentioned: go out and enjoy! Best regards, John B. Paine III,
>jbp3@comcast.net, Midlothian, Virginia
>
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