Dims: 1.4" x 1.3" x 1.1" (3.6 x 3.3 x 2.8 cm)
Wt: 2.48 oz. (70.3 g)
Malacacheta, Minas Gerais, Brazil
Upon first glance, I thought that this was simply a piece of moonstone, or another related feldspar. This Andalusite specimen does look similar. However, it is definitely Andalusite, as I saw a small piece that had chipped off of another specimen, which had the obvious pleochroism that one expects of this mineral. This particular specimen consists of an irregular chunk of material that shows crystalline tendencies, but lacks a discernable orthorhombic form. It has a reddish-brown coloration and a luster that ranges from waxy to almost vitreous. Though as a whole the specimen is opaque, it does show clarity in several spots that extends a few millimeters into the stone. It is so heavily internally-fractured, however, that one could not hope to see through it. The light that passes through these thin, transparent layers is often reflected back, showing what appears to be a strange iridescence.