I had the opportunity to visit the Kimberlite deposits and diamond mine that are in the eastern part of Elliott County with a group of seventh graders.
found in Kimberlite.
Kimberlite is formed as semi liquid magma from deep in the earth's mantle forces its way up through the mantle and then the crust. As it moves through the rocks above it chunks break off and are mixed in. The first picture shows the dark black/grey Kimberlite and several lighter colored inclusions (xenoliths). Other minerals are formed from the elements found in the mantle. The other pictures show a piece of translucent yellow/brown/green olivine and a bit of dark brown/black mica that are common in this Kimberlite. Other minerals that have been found include: garnet, tourmaline, hornblende, magnetite, ilmenite, chromite, titanite, rutile, actinolite, staurolite, quartz, feldspar, zircon, topaz, monazite, xenotime, and fluorite.
Arkansas at the
Crater of Diamonds
State Park you can still find
diamonds that were left in the soil formed by the breakdown of
And of course Kimberlite is named from the famous diamond bearing deposits in South Africa where most of the world's diamonds are mined.
Unfortunately according to the University of Kentucky no diamonds have ever been authenticated from the Elliott County deposits.
But several people have told me of friends or relatives that found diamonds ranging in size from a walnut to a fist.
some of the
equipment left by
the Kentucky Kimberly Diamond
Company which operated here starting in 1906.
The mining operation started with excavated rock and soil being passed through a crusher of which only the foundation remains.
crushed rock and
soil were then
mixed with water in the device pictured
below to make it easy to separate the very fine material from the rest.
was then passed
through the screening box where
it is separated into course, fine, and very fine fractions.
from the screening
process would be passed through
an X-ray fluorescence sorting process to separate the diamonds from
Back then the sorting was done by hand.
came to the
site the students
had high hopes of finding a diamond
that would make them rich.
set to work
sifting through the
gravel along the stream bed. Some
waded right in.
none of the
diamonds (not that they told me about
anyway) they all learned a bit of the history of the county and a bit
What they did find were Garnets. Most found a few, one student found 9 another 15.
Here are three that were found in the stream.