Calcite with Pyrite

A fabulous small miniature from the Příbram Mining District in the Czech Republic which demonstrates some remarkable variations in the crystal habits of Calcite.  A three-sided, trigonal Calcite crystal, 5.5 cm long, leans at a forty-five-degree angle on its cleaved base.  Every face is built from translucent to gemmy Calcite crystals, each of between 2- and 5-mm width and displaying pentagonal faces with a brilliant glassy lustre.  These are overgrown with sub-millimetre micro crystals of brassy, slightly iridescent Pyrite, completely coating two of the three faces and only partly on the third.  A terrific and showy Calcite with Pyrite from Příbram.