Microcline….or Anorthoclase in XPL😁

Found this weirdo muscovite grain in a thin section of the Dawson Formation when we were playing around with sedimentary petrology slides instead of studying for lab final… (at Benson Earth Sciences - UCB)

Yup. No filter. This little guy is one of many fluorescing fluorite specimens available at mi amiga’s etsy crystal shop, Phenomenal gems.. Need to try and cop a piece for myself. very cool 😎

Gneiss (at Chatfield Reservoir Dog Park)

Macro image of an apatite xtal in some matrix

Prehnite ball with (what i think is) tourmaline and epidote….. This crystal is for sale at: http://www.etsy.com/shop/PhenomenalGems

A sandy Morrison Fm outcrop with poor medium-scale trough cross-bedding of coarser lags. Note pencil for scale (at Dakota Ridge Trail)

Captain and Petey on the gneiss🐾😄 (at Chatfield Reservoir Dog Park)

Me thinks she be a meta-sed staurolite schist (at Benson Earth Sciences - UCB)

PPL vs XPL of a kyanite meta-sed schist…. Densely fractured grey xtals are kyanite; euhedral dark brown-green xtal in middle-left is tourmaline that displays unusual complete extinction (even when rotating the stage) in XPL; brightly colored xtals are muscovite; there’s also biotite and quartz