This is a specimen featuring gobbinsite, chabazite-Na, and (odblall) cryolite, all of which are rare minerals at MSH - except in the core of the Poudrette pegmatite , where this specimen is from. The chabazite from this find was confirmed via EDS and XRD. (See the “Analysis” tab. But this is not the specimen that was analyzed.) The cryolite was also confirmed via EDS (on this specimen).

The gobbinsite has the bizarre appearance typical for MSH. The crystal (or aggregate)  in the center of the first pair of photos (FOV 1.9 x 2.6 mm) is small (0.7 mm), but very characteristic. There are at least three other gobbinsite crystals (or aggregates) in the photo. The pinkish, frosted, disks are chabazite-Na.

The second pair of photos (2.4 x 3.0 mm) shows more gobbinsite and chabazite. One of the larger gobbinsites (0.9 mm) has a habit similar to the one in the first pair of photos. The one next to it is more of a “mess” – but it still has the characteristic “spiky” appearance.

The next pair of photos (FOV2.0 x 3.0 mm) shows some isolated chabazite discs ca 0.65 mm in diameter. Unlike the others, these are colorless, not pink. They are translucent but the “scaly” growth patterns give them a frosted appearance – characteristic of chabazte-Na at MSH.

The next pair of photos (FOV 4.3 x 6.4 mm) shows some of the cryolite. It is rather unusual looking. Some parts appear to be heavily etched (“scalloped”). Because of the appearance, some of the material shown in the photo was sacrificed for EDS, which showed either cryolite or dawsonite. Since the material doesn’t fizz in HCl, it must be cryolite. I have added a scan for “known” cryolite for comparison. The white crust on the cryolite consistins of an unidentified (Na,K,Ca)(Si,Al) zeolite. (See the “Analysis” tab.) On another specimen form this find, tiny white octahedral can be discerned, suggesting dehydrated gobbinsite. 

The “scalloping”- extreme etching - of the cryolite is shown in the next photo (FOV 2.3 x 3.0 mm). The gobbinsite appears to be growing in some of the etch cavities.

Single item shipping weight is 3.1 oz (88g). For shipments outside the USA, up to a total weight < 8 oz (225g), this can be combined with items from this or other auctions for the same postage.

Within the USA, postage increases by about $0.20 per ounce. Above 13 oz, I will use Priority Mail ($9.25 including packing).