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Gibbsite

Gamba, Brazil

Small cabinet, 5.5 by 4.1 by 2.7 cm

$80 - Order Form

Gibbsite is aluminum hydroxide, a major component of bauxite aluminum ore. This specimen is a curious botryoidal crust of gibbsite, looking much like chalcedony. With a French BRGM label, and a Joseph Urban collection label. Although not a rare mineral, rich gibbsite specimens are very scarce. The iron-staining could be removed chemically, but that decision resides with the buyer. A photograph of the side of the specimen shows the underlying texture and white color of the mineral. This is the only such specimen I have ever seen.