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The dolomite grain size appears bi-modal: larger grains about 90 - 100 mm in size and smaller ones at 5 - 10 mm. There are also a large number of mm sized inter-stitial calcite crystals which appear to cement the larger crystals together, although rather poorly. The smaller grains do not fill the inter-stitial cavities, giving the rock a fairly high porosity.
The dark grains have a pearly lustre and vary in size from a few mm up to about 30 mm. In some of the larger grains the colouration is zoned from whitish translucent at one end to dark semi-translucent purple at the other. Under crossed polars the darker translucent parts show bi-refringence. (Calcite ??)
Hand samples fracture under the hammer quite easily and the conchoidal looking edges are very friable.
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