The June 2004 meeting of the Florissant
Scientific Society was held at the
new Florissant Public Library at 12:30. Ed Raines presented the second in
his series of slide programs about the geology, history, and mineralogy of
Creede, in Tom Steven's honor. Members present included Tom Steven, Dan
Shaw, David Atkins, Beth Simmons, Jeff Bartley, John Ghist, Bill Dexter.
Visitors and new members included Sylvia Pettem Raines, Sally and Hank
Martens and Patricia Mosch. Ed's exquisite slides of the unique minerals and
crystal growth habits of Creede captivated all. We learned that "Hopper"
crystals grow in a supersaturated solution and can occur in galena.
Sphalerite grew in stalactites, then was coated with crystalline
chalcopyrite. There were specimens in which the original mineral had
dissolved, but the crytalline structure was preserved in the overgrowth. Ed
showed slides of acanthite growing within his specimens in his cases,
proving that it doesn't take long for these metals !
to change from one form to another. Conjecture ensued about cyclic
deposition and Tom suggested that a possible environment might have been a
geyser basin, where pockets would have been emptied of fluid, the
stalactites formed, then the solution refills the pockets and the second
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