GAHNITE
Specimen gah-2

Dims: 2.5 x 2.2 x 1.5" (6.4 x 5.6 x 3.8 cm)

Wt: 5.3 oz. (148.8 g)

near Otjiwa, Namibia

Dozens of Gahnite octahedrons are embedded in the rough brown host rock of this small hand specimen. They range in diameter from less than 0.1" (3 mm) to nearly 0.4" (1.0 cm). Most of the exposed crystals are either damaged or broken, but there are several crystals which are mostly embedded in the host rock, and are likely in excellent condition. Where intact, they have excellent octahedral form, with well-defined edges and clean faces that possess a rather dull submetallic luster. All have a basic black color and are completely opaque. The host rock in which they rest is heavily rust-stained and contains a substantial amount of calcite. There are also several misshapen books of biotite present.

Dims: 1.2 x 0.9 x 0.9" (3.0 x 2.4 x 2.4 cm)

Wt: 0.5 oz. (13 g)

Crazy Sphinx Mine, Helena, Montana, U.S.A.

This thumbnail consists of a single Gahnite crystal with a small amount of a pale host rock present. The crystal makes up almost the entire bulk of the specimen and is in very good condition, showing only one or two areas of old damage and one small area of new damage. It shows surprisingly good octahedral form, though the crystal is warped. It has the standard dull blue color with a hint of green and a waxy luster, and is completely opaque. It sits loosely inside a plastic thumbnail box.