19BL07A Bournonite
Machacamarca District (Colavi District), Saavedra Province, Potosi Department, Boliviah
6.2x 3.9x3.9 cm
$435
A cluster of unusually bright and lustrous bournonite crystals on matrix. The pieces from this find really stand out for their combination of thickness and luster-- the brightness of these crystals is not something that is common from this location-- they tend to be tarnished or have overgrowths of sphalerite or miscellaneous antimony minerals.
The last time this mine produced particularly good crystals was 2012-- there was another find of large blocky crystals around 2015, but they didn't have much going for them as far as luster was concerned, nor did I see any on matrix.
