As Marlo pointed out, Florida has an active limestone industry,
though it is not nearly
as big a business as it was in the 1950s-70s. Back when I was growing
up in Miami,
one of our favorite activities was going to the limestone pits where
you could almost
always find calcite, a soft gemstone which appears like a smaller
version of the quartz
crystals. Occasionally a geode was found, split open to reveal the
sparkling calcite
interior. I had quite a collection in my teens. Most of those areas
are now housing
developments, but in the "old days" they covered many acres. Back
then, nuisance
lawsuits didn't prohibit anyone from "prospecting." As long as we
stayed away from
the active digging, nobody ever said a word, and there was so much
calcite to go around
that we could have trucked out several big loads without making a
dent in the supply.
By around 1974, most of the digs were fenced in, but we found calcite almost
everywhere that there was construction. The land now occupied by
Florida Atlantic
University was a great place where you could find nice big crystals
around the banks of
the canals, along with many fossils. It was also a nice spot for
Neritina virginea.

Jim

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