MSH is famous (notorious) for its huge “beastiary” of strange and remarkable pseudomorphs. This is an example of a large (18 mm on edge) pseudomorph of catapleiite after (probably) pseudo-octahedral “eudialyte”. The pseudomorph sits on microcline, part of which is euhedral, and there a few large, broken, blades of aegirine.

The surface of the pseudomorph is further encrusted by tiny (0.3 mm) fluorite cubes and small  (0.7 mm) rhodochrosite rhombs , so the catapleiite itself can, for the most part, be seen only on the bottom of the specimen. The last photo (FOV 6.9 x 4.6 mm) shows some of the fluorite and rhodochrosite.

Found April 1997. Probably from the Poudrette pegmatite.

This is not going to be the prettiest “rock” in your collection, but perhaps more interesting than all those big aquamarines.

Single item shipping weight (small box with MM case) is 2.8 oz. Up to a total weight of 8 oz (225 g), this could be combined with other items from this or future auctions for the same postage. If you wish to keep an “open box”, let me know. Please see my "Shipping Policy" for details.