This is a specimen of cubes of white and clear orschallite in association with white fibrous picropharmacolite. In all, twelve micro-crystals of the orschallite are on and in a very fragile matrix. Therefore we did not mount identifying arrows. 

When viewed under the microscope you will find a cluster of three glassy, clear, triclinic wedge-shaped orschalite crystals. This form is a depature from the normal pseudocubic form. The fourth image illustrates the dominant 0.7mm crystal on top of two others, all on needles of picropharmacolite.

Elsewhere on the sample are nine normal (but some distorted) white pseudocubic crystals to 1.0 mm, some with clear patches.

The clear wedge shaped crystals are much rarer. As far as we are aware, there are only two samples with these clear crystals in existence and this is one of them.

We had single crystal XRD analysis performed on the triclinic wedge-shaped form which confirmed the species as orschalite. 

The material was found in a boulder of deeply weathered dolomite from the upper portion of a silver vein. The predominant mineral in the boulder was white picropharmacolite as white acicular crystals to 0.5cm filling fractures and vugs in dolomite.

See the EDS pattern on the analysis tab.