FLUORITE
Specimen flu-58
$ 28.00Dims: 1.7" x 1.2" x 1.0" (4.3 x 3.0 x 2.5 cm)
Wt: 1.32 oz. (37.5 g)
Naica, Chihuahua, Mexico
A very simple thumbnail specimen, this piece consists of two separate and distinct clusters of Fluorite crystals resting on a crystalline sphalerite base. The larger cluster measures approximately 1.0 x 0.9 x 0.8" (2.5 x 2.3 x 2.0 cm), and the smaller has dimensions of 0.6 x 0.4 x 0.4" (1.5 x 1.0 x 1.0 cm). Each Fluorite cluster appears to be composed of many intergrown cubic crystals that are all aligned with each other. The largest of these crystals measures about 0.3" (8 mm) across its only completely visible face. All are colorless, reasonably clear, and have a vitreous luster on their faces. All of the visible edges of all the crystals in both clusters are truncated by secondary faces. Upon close examination of the largest crystal face in the larger cluster, I noticed that there are fibrous, needle-like crystals visible below the surface. Further examination showed that such crystals are visible in a few other places on the cluster- I do not know their composition. The sphalerite base on which the clusters rest appears to be made up of several incomplete and intergrown tetrahedral crystals that have the standard dark brown color, opacity, and adamantine-to-metallic luster.