Dims: 4.4 x 3.5 x 0.6" (11.2 x 8.9 x 1.5 cm)
Wt: 8.46 oz. (240.1 g)
northern peninsula, Michigan, U.S.A.
This hand specimen consists of a slice of a large columnar piece of Satin Spar, a variety of Gypsum that possessess a compact, fibrous habit. This slice is roughly polished on both cut faces, but many scratches are still visible. One can see evidence of its habit along the side faces, which are heavily striated. The Satin Spar is colorless and transparent, and though it contains many internal fractures, these are directionally aligned so that they provide little interference when viewing the piece through either of the polished faces. Thus, it is quite clear, enabling one to see print or designs very easily through it when it is placed on top of them. The optical effect is not quite the same as that of fibrous, compact ulexite, but it is similar.