MSH is the TL for horváthite-(Y). It has now been found in an extremely rare occurrence in the nearby Demix-Varrenes quarry, but that is the only other known locality. The best and richest specimens are from MSH. This is a small, but richly covered specimen. Altogether the horváthite forms a continuous “carpet” ca 9 x 15 mm.
Horváthite is always twinned. The two most common habits are elongated, radiating, lath-like twins, and more equant, doubly “terminated”, stubby, chisel-like twins – as on this specimen. The horváthite on this specimen is essentially colorless with a very faint pinkish tinge. In aggregate, the horváthite can look fairly pinkish (just like deep water looks blue or green). (The elongated twins tend to be pale beige or pinkish-beige.)
Horváthite is generally a difficult mineral to photograph due to lack of contrast with the matrix or other minerals. That is particularly true for carpets of randomly oriented “chisel” twins of the type on this specimen. Only where the horváthite juts out on a prominence or edge of the specimen is it possible to get a contrasting background that allows for a clear view of the morphology.
The first pair of photos (FOV 1.15 x 1.55 mm) shows one of the few spots on the specimen where I was able to photograph with a dark background. However, the crystals are small (<= 0.6 mm), and at the high magnification required, the optics on my scope break down and cry rainbow tears allover the images. To get rid of the chromatic aberration, I had to resort to Photoshop tricks, which made the images even less sharp. Nonetheless, the photos provide a “clear enough” view of what individual twins look like.
The second pair of photos (FOV 2.35 x 3.45 mm) shows a small part of the “carpet” at lower magnification. The largest crystal here is 0.65 mm. The “carpet” is essentially 100% horváthite. (There may be a tiny sabinaite crystal or two but I’m not sure.)
The third pair of photos (FOV 4.1 x 6.75 mm) shows a bigger patch of the “carpet” ay half the magnification. Here too, the “carpet” is essentially all horváthite.
In the full-view photo, all of the slightly pinkish area is horváthite
Single item shipping weight (with TN case) is 3.2 oz (91g). For shipments outside the USA, up to a total weight < 8 oz (225g), this can be combined with other items from this or other auctions for the same postage. If you don’t need the TN case, you can save about 0.3 oz in weight which could be used for something else.
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.
