Measurements: 57 x 49 x 36 mm
Description: Two amethyst quartz crystals (with some smoky colouring included) and a feldspar crystal sit on a matrix of basalt rock and feldspar.
The main crystal measures ± 34 x 20 x 20 mm. There are some minute indentations on the termination facets, probably caused by some other mineral that had previously been attached, and then weathered away over time.
Both quartz crystals' terminations appear to be undamaged, but the maincrystal has a stable flaw near its base. The matrix has been trimmed at the bottom, to display better on a flat surface. Damage is limited to the edges of the specimen.
Weight of Specimen: 72.4 g
Chemical Composition: SiO2 (quartz) KAlSi3O8 (feldspar)
Hardness on Mohs Scale: (quartz) 7 (feldspar) 6 - 6.5
Location: Brandberg, Namibia.
Specimen Code: NBB 016
US $ 75