Monday,
September 13, 2010
6:00 - 7:30 pm
Pellissippi
State Technical Community College
10915 Hardin
Valley Road, Knoxville
Faculty/Staff dining room
adjacent to the regular meeting room (Annex Cafeteria)
SEPTEMBER PRESENTATION
Graves Mountain,
Georgia
A Brief Review of an Average Kyanite Mine And
World Class Mineral Collecting Locality
by
Travis A. Paris
Geologist, Aggregates USA, LLC
Graves Mountain is a small
monadnock rising above the Piedmont of eastern Georgia in western Lincoln county
Georgia. It is comprised mostly of quartzite with significant localized
quantities of kyanite which were mined in the 1960-1990 period.
The mountain gained its notoriety not from the kyanite deposits
themselves, but from the rutile crystals found mainly in the
central part of the mountain. These were discovered
in the mid 1850&rsquos by Dr. M.F. Stephenson and sent to
Professor Charles Upham Shepard at Yale University, who published
an article in 1859 on the complex twinning of the rutile and
further distributed the samples. German crystallographers
studied the crystals extensively and published a number of
articles with detailed crystallographic drawings. Further
exploration revealed the presence of the kyanite, pyrophyllite,
and lustrous blue lazulite. Mining of the lazulite quartzite took place in
the late 1800s, with material being cut into ornamental pieces and jewelry by
Tiffany & Company. Collecting has continued through the years, with the
identification of a suite of rare phosphate minerals in the early 1990s, as well as other minerals.
Graves Mountain is not &ldquounique&rdquo, but neither is it common. It is part of a series of
monadnocks extending northeast into Virginia. These
monadnocks are all characterized by mineral assemblage of
quartz+kyanite(+andalusite)+lazulite +pyrophyllite+pyrite+topaz
and suites of rare phosphate and sulfate minerals.
The origin of the deposits has been and is being debated by
numerous writers. Most ascribe the kyanite to regional
metamorphism of aluminous sediments, some to regional
metamorphism of altered volcanics, and a few to volcanic,
epithermal processes. I subscribe to the epithermal theory
and will briefly describe my views of the formation of the
deposit.
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