27048: Gypsum variety Selenite (twinned) -
$26 Lavrion Mining District, Lavreotiki, East Attica, Attica, Greece Cabinet - 10.0 x 6.9 x 1.0 cm 100 grams Specimen status: Available Send an email with specimen number to order A flat cleavage plate of colorless,
very clear gypsum. (The find consisted of large
uninteresting gypsum masses, so these were cleaved to
better show the internal structure.) Although the term
selenite is **widely** misused, this gypsum example is
quite clear and transparent, and hence worthy of the
moniker. At the center is a hazy inclusion stripe,
consisting of at least unidentified minerals: an amorphous
muddy brown (limonite?), a black, somewhat iridescent,
octahedral (?) species (cuprite?), and a white,
nonfluorescent, crystalline mineral. This stripe is also
the nexus point of twinning; angled growth lines radiate
away from this central point. Reminiscent of the central
line in faden quartz. Interesting under the microscope. A
must for the collector of twins, of gypsum or of Greek
minerals. From finds in 2016 or 2017.
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