This is an interesting specimen of a Calcite cluster once called the "Mariposa" habit. These are scalenohedral crystals to 3cm some coated with a thin veneer of chocolate iron oxide. There is a second generation of colorless, complex Calcite on top of the aforementioned Calcite. A third generation can be seen as smalle 1-3mm Calcite crystals occupying the terminations of some of the crystals. Acquired by Hampson in 1971. These Calcites are rarely offered on the market these days. It is a classic for Mexico.