This is a sharp pair of parallel-growth terminated elpidite crystals, with micro rhodochrosite in association.
This specimen has an incomplete termination face on one side. I can’t say whether that happened naturally in the pocket, or not. It is other wise in excellent condition (no damage) and priced accordingly. The incomplete area has the same matte lustre and same colour as the complete termination faces, so does not jump out in that way. I wanted to be able to offer it despite this imperfection because it is amazing to have a sharply-terminated elpidite crystal, and the imperfection can be angled away from the viewing angle – it’s a great price for an elpidte from the pocket that produced the best terminated crystals known.
Elpidite is quite rare globally, and relatively few high-quality specimens are known. At Mont Saint-Hilaire, elpidite has been encountered periodically, almost always as bundles or jumbled groups of intergrown crystals lacking well-defined terminations. However, a 1990 pocket yielded the best terminated single crystals of elpidite known, and these specimens are from that pocket.