THE MINERAL BERTHIERITE

Dims: 2.1" x 1.3" x 1.1" (5.3 x 3.3 x 2.8 cm)

Wt: 1.18 oz. (33.6 g)

Herja, Romania

Not only is the chemical composition of this mineral similar to stibnite, it looks like it, too! This small hand specimen consists of at least 3 intersecting clusters of Berthierite; one is much larger than the rest, having dimensions of 2.0 x 1.3 x 1.0 (5.1 x 3.3 x 2.5 cm). The other clusters are quite small, and intersect the larger cluster near its base. The crystals all have the form of fine, orthorombic needles that are tightly packed into acicular sprays. Like most metallic sulfide minerals, they are opaque and have a metallic luster. Their color is a medium-dark gray. Though I cannot tell how many of the crystals have been broken, the specimen is in generally good condition, showing a small amount of noticeable damage to two of the clusters. There is no host rock or other foreign material on the specimen.

Dims: 3.7 x 3.6 x 1.5" (9.4 x 9.2 x 3.9 cm)

Wt: 8.6 oz. (245 g)

Herja Mine, Maramures, Romania

Several Berthierite sprays are partly embedded in the calcareous base of this cabinet specimen. These sprays usually do not exceed 0.5" (1.3 cm) in either length or diameter, but one is very large, measuring nearly 2.7" (6.9 cm) long- it is also the least complete of the sprays, showing heavy damage and considerable breakage. The smaller sprays are generally better protected and more complete, and close examination will show a complex network of crystals that fills crevices in the stalactitic calcite base. The Berthierites have good orthorhombic, needle-like form and the standard dark, silvery-gray color and metallic luster of their species. The calcite base is almost more impressive than the Berthierite, as its stalactitic protrusions are well-formed and coated with countless tiny trigonal calcite platelets.

Dims:2.6x1.2x1.1" (6.6x3.0x2.8 cm)

Wt: 1.4oz. (40g)

Herja, Romania

This is an exceptional radiating cluster of fibrous berthierite crystals. There is no matrix with this specimen-it is all berthierite. There is a tiny amount of glue on the base of the cluster where it was once glued to a base. There is no damage to this specimen.

Dims: 2.13x2.36x1.38" (5.4x6.0x3.5cm)

Wt: 2.99oz. (84.7g)

Baja Sprie, Romania

This is a beautiful and unusual specimen of berthierite. It consists of several fibrous clusters of acicular needles, the largest of which looks rather like the tip of a cat's tail (in shape and in the visual texture of the needles). The color is a dark gray-brown, but these clusters also have an irridescent appearance. The individual crystals have a metallic luster, and sparkle in the light. Lastly, the parallel needles are fine enough to make the specimen look chatoyant.