Dims: 1.3" x 1.0" x 0.8" (3.3 x 2.5 x 2.0 cm)
Wt: 20.2 g
Mistake Mine, Yavapai County, Arizona, U.S.A.
The base rock of this particular specimen appears to be made up of goethite, as it has the proper brown coloration, but it is not powdery and messy like goethite often is, and it has a faint sparkly sheen that indicates that it is coated with some form of microscopic crystals. Coating part of this host rock is a thick, almost botryoidal layer of acicular, radiating Ramsdellite crystals. These crystals appear to be in excellent condition, with no apparent human-induced damage. They have reasonably good form, looking like small spikes that radiate out of the base. None of these crystals exceeds 3 mm in length, and all have a dark gray color and a metallic luster. They remind me strongly of pyrolusite.