raw emerald gemstone crystals inside feldspar rock with molybdenite, mica and apatite inclusions on black background.

apatite article background black blotches blue catalogue closeup crystal dark detail education emerald encyclopedia euhedral feldspar felspar fossil gem gemstone geological geology inclusion isolated material mica mine mineral mineralogy molybdenite museum natural ore piece poster raw rock russia science semiprecious shape shiny stone surface textbook texture ural website