Epistolite is a rare mineral, found in only a few alkaline localities worldwide.

Material from this find was analyzed in three different labs by various methods, including long exposure XRD and microprobe (among others). All three concluded that the stuff is epistolite. (Some preliminary work indicated vounnemite, but, in the end, the consensus was epistolite. Apparently distinguishing epistolite from shkatulkalite and vuonnemite is a lot trickier than one might think. For one thing, they are often intermixed.)

The crystals on this specimen are small. The aggregate shown in the first close-up photo is only about ½ mm x ¾ mm, and some crystals are partial. Nonetheless, this is epistolite, which is a great rarity in the Saint-Amable sill (and not exactly common anywhere else). Moreover, unlike most of the crystals from this find, they actually look like epistolite from, say, MSH. Also note that, unlike most crystals from other localities, these are free-standing.

The next pair of photos (FOV 1.6 x 1.3 mm) is a “closer-up” view of the same crystals.

There are a couple of equally small partial crystals in another part of the cavity (not shown).

Single item shipping weight  4.1 oz. Outside the USA, the stated postage and packing rate applies up to a total weight of 8 oz (225 g).

Within the USA, there is a nominal increase of $0.20 for each additional ounce; above 13 oz, I will use Priority Mail. Up to 16 oz, the “own box” Priority rate (including packing) is ca $9.25 (varies by destination).