Epididymite with Aegirine and Rhodochrosite

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This miniature specimen features a 3 cm wide twinned platy Epididymite with Rhodochrosite and Aegirine. Mont Saint-Hilaire is renowned for having produced exceptionally well-crystallized Epididymites - some of the world's best - but most are in the scale of millimetres, rather than centimetres. This lovely twinned crystal is not just extremely large, but maintains great crystal form and displays the growth-lines wonderfully well on both sides. It is quite wide, and glassy, mostly colourless, but with a hint of pale cream tones. It is also nice to have matrix attached to both sides, rather than just a loose single crystal as many of the larger crystals are. The Rhodochrosite occurs as aggregates of pale pink rhombic crystals either side of the Epididymite crystal, along with small black prisms of Aegirine. This provides a nice contrast in colour. A small amount of white matrix is probably Microcline. If you are not familiar with Mont Saint-Hilaire - although I am sure you are - it is a mineralogical freak of nature, with a recorded 439 species and is type locality to a staggering 73 species. For many years two quarries worked adjacent to one another, the Poudrette and De-Mix, only separated by an unexcavated demarcation wall. Once this was mined out, the quarries amalgamated, so it is now the convention to name the whole quarry as Poudrette. It is not known which quarry this specimen came out of at the time of mining (i.e. either Poudrette or De-Mix), so it is simply given as Mont Saint-Hilaire. This is an extremely fine example of one of the sought after rare species from this famous quarry.