Sphalerite Borieva Mine, Madan District, Smolyan Oblast, ...
Description: Sphalerite Borieva Mine, Madan District, Smolyan Oblast, Bulgaria 8.0 x 9.0 cm. Lustrous, black sphalerite crystals to 2.5 cm. with slender, transparent quartz crystals. Mined in 2006.