Calcioancylite-(Ce) pseudomorph after Remondite (very rare)

Item Description

Here we have a rare pseudomorph from the famous Poudrette Quarry at Mont Saint-Hilaire, one of the world's most diverse and unique mineral localities. Not only is this locality well-known for its plethora of unique species, this complex nepheline-syenite / pegmatite locality has produced some of the most distinctive pseudomorphs, featuring replacements that aren't seen anywhere else in the world. This piece is a notably rare example of grey Calcioancylite-(Ce) pseudomorphing after Remondite, showing large, distinct, stout crystals among the largest we've had to offer in the auctions. I've only seen a select few of these over the years, and I found that there was a write up of this material in the July/August 2000 of the German mineral magazine, Lapis for reference. They were found in the late 1990s, and I was told that they all came from a single pocket. Don't miss out, as we don't have another to offer.
From the collection of Dr. Robert ("Bob") Byers of the San Francisco area. Bob is a spinal surgeon, who started collecting minerals as a boy when his father took him on geology field trips. Bob acquired this specimen from Frank and Wendy Melanson in 2009. The original value 15 years ago was $150, but I could easily see it closer to the $1,000+ range today