This specimen features very nice frosted plates of chabazite-Na. Chabazite-Na is a rare mineral at MSH – except in the core of the Poudrette pegmatite, which probably produced more than 99% of the chabazite-Na at MSH. (László Horváth - private communication.) However, most of that chabazite is apparently in the form of nearly featureless ‘golf balls’. Platy crystals such as these appear to have been much less common.

It can be very difficult to distinguish chabazite from gmelinite at MSH – even with EDS. This specimen was analyzed via qualitative EDS, which suggested chabazite-Na (see the “Analysis” tab), and via PXRD, which confirmed “chabazite”. To absolutely prove that this is chabazite-Na, would require further (expensive) analysis.

Note: According to the most recently published MSH rarity tables (Lapis and Rivista 2000), the chabazite found in hydrothermal pegmatites (i.e. the Poudrette pegmatite) is chabazite-Ca. However (private communication) this was based on preliminary results from EDS, which can often be misleading. (For one thing, Ca is much easier to detect than Na, so raw peak heights are a poor guide.) Detailed analysis has shown that it is chabazite-Na instead. In the current case, the apparently high K peak in the scan  is similarly misleading.

FOV in the first pair of photos is 4.4 x  6.8 mm. Individual chabazite plates are <= 1 mm.

The second pair of photos (FOV 3.4 x 2.5 mm) is a close-up of another part of the specimen. The color of the plates in this pair of photos is different. In part this is because the actual color varies from faintly pinkish to colorless to faintly violet. But I also had a lot of trouble with color balance for this subject.

The fifth photo (FOV 6.4 x 3.7 mm) is another attempt to get the color right. Probably the most accurate colors are the ones in the last (full-view) photo.

Single item shipping weight (with MM case) is 2.8 oz (79 g). 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 for total weights up to 13 oz ranges from $4.25 to $6.50 (including packing etc) regardless of destination. Above 13 oz, I will use “own box” Priority Mail. The rate, including packing, varies by destination from $7.25 to $9.50.

See my updated “Shipping Policy” for details.