Ernstite pseudomorph after Childrenite (very rare) (ex David Burgess Collection)

Item Description

A really cool and incredibly hard to find pseudomorph from this well-known Brazilian locality featuring a notably large "sword"-shaped crystal group of what was once Childrenite that has been pseudomorphed by the very rare manganese iron phosphate, Ersnstite. The rust colored Ernstite is completely coating the outer surface, and has nearly replaced the Childrenite throughout, though I can see a tiny bit of remaining Childrenite at the base where the crystal is contacted. This particular material is incredibly rare worldwide, and this piece is the LARGEST example that we've had to offer. Fine quality all around, with no damage (save the base where it was removed from the pocket wall), and very impressive in terms of size and crystal form / sharpness. Valued at $950. From the worldwide collection of David Burgess (1951-2016). David was a prolific species collector from Newington, Connecticut, and the namesake for the extremely rare cobalt arsenate species Burgessite, which he discovered.