ZINNWALDITE
Specimen zin-5

Wt: 1.7 oz

El Paso Co., Colorado

Here on this specimen, nestled between the loving arms of a beautiful, sea-green cluster of Amazonite, lies a rare member of the Mica group known as Zinnwaldite. It can only be distinguished from Muscovite through chemical laboratory analysis, as it simply has a considerably higher percentage of iron and magnesium. It is in the standard Mica "book" form, and maybe looks a tad darker than Muscovite. Hitching a ride is a smidgen of Cleavelandite, a form of Albite Feldspar. This is the only one we have- avoid the free-for-all.

Dims: 3.7 x 1.9 x 0.9" (9.5 x 4.8 x 2.3 cm)

Wt: 5.7 oz. (163 g)

Sentinel Rock, El Paso County, Colorado, U.S.A.

This large hand specimen consists of a "book" of Zinnwaldite mica that is in excellent condition. Its pseudohexagonal form is likewise excellent, and though its form is not complete, it is not caused by any form of damage. The book has a rather dark brown color and the standard pearly, micaceous luster, and is opaque, though individual sheets would likely be transparent. There is almost no host rock present.

Dims: 1.6 x 1.4 x 1.1" (4.0 x 3.5 x 2.8 cm)

Wt: 1.2 oz. (33 g)

Londonderry, Victoria, Australia

This small hand specimen appears to consist of part of a radiating spray of highly compact Zinnwaldite blades. These blades appear to reach lengths of 1.5" (0.8 cm) and are impossible to define as individuals due to their intensely compact nature. The material strongly resembles all micas in its flaky habit and pearly luster. There is no host rock present.

Dims: 1.2 x 0.6 x 0.1" (3.0 x 1.6 x 0.4 cm)

Wt: 1 g

Zinnwald, Erzebirge, Czech Republic

This thumbnail piece consists of a misshapen Zinnwaldite blade. The blade is in fair condition and appears to be a shard from a larger crystal. It shows no definable form, though it is definitely crystalline in nature, and has the classic brown color and pearly, micaceous luster of its specie. It is also dimly transparent. There is no host rock present, and the piece is affixed inside a plastic thumbnail box with a removable putty.

Dims: 3.7 x 2.1 x 2.1" (9.4 x 5.4 x 5.3 cm)

Wt: 9.3 oz. (263 g)

Sentinel Rock, Colorado Springs, Colorado, U.S.A.

A single, large Zinnwaldite "book" extends from the albite base of this cabinet piece. The book is in excellent condition, showing little damage, and has dimensions of 1.5 x 1.2 x 0.8" (3.8 x 3.0 x 2.0 cm). It shows excellent monoclinic, pseudohexagonal form and the classic perfect cleavage. Its color is black-brown and its luster is the standard pearly. A few white microcline crystals are also embedded in the albite base.