selenites
Hi, Bill–
Apatite being known at the Harding mine, go for it! It fits the hardness and
fluorescence. Perhaps your 90 degree cleavages are crystal faces? A
termination would often be a flat face at 90 degrees to one of the prism faces.
I do not know about your "stress markings" – phantoms, maybe?
A piece to look at would be welcome and might clinch the ID, provided you do
not break the specimen up trying to get it! If you decide to chance it, I am
at 12831 N Stratford Dr #150, Oklahoma City, OK 73120.
According to Gemstone & Mineral Data Book (Sinkankas) useful liquids
are hexane (.66), heptane (.68), isopropanol, methanol, or ethanol
(.79 – surely these are 200 proof), acetone (.79 again; nail polish
has it, but again maybe not concentrated enough), kerosene (.80-.84),
amyl alcohol (.81), mineral oil (~.84), toluene (.867; do not become
a glue-sniffer!), amyl acetate (banana oil), ethyl valerate(.88), and
oops, there is another page so I am not going to type them all, just
some one might find at home: water (.998) diethylene glycol
(antifreeze) or salt water 1.12, glycerine (1.26), and carbon
tetrachloride (1.541). The rest tend to be like cadmium
borotungstate, diiodomethane, and other goodies.