This specimen features two rare minerals, nenadkevichite and villiaumite, not from MSH, not from Kola, nor from Aris! Instead, the specimen is from the – unjustly - lesser known Demix-Varrenes quarry, about 20 km from MSH (as the crow flies).
Both minerals are exceptional for the locality. The nenadkevichite occurs as numerous, very small, but excellent, water-clear, tabular, pseudo-hexagonal crystals. The villiaumite crystals are about as close to “real” crystals as I have seen from here. They are both etched, but one is only slightly so.
In addition to the villiaumite and nenadkevichite, there is some sérandite, a couple of unidentified minerals (probably nothing to get excited about), and very minor pink eudialyte, yellow zakharovite and green aegirine. Everything sits on microcline and/or natrolite.
The first pair of photos (FOV 1.4 x 1.8 mm) shows perhaps the best nenadkevichite crystal. It is only 0.35 mm wide, but it is very good for the locality. There are numerous other nenadkevichite crystals on the specimen.
They can be seen (though not very readily at this scale) at top right in the next pair of photos (FOV 4.3 x 6.6 mm). These photos also show the best villiaumite crtstal (center), one of the UKs (at the red arrow,) and a bit of eudialyte, zakharovite, and aegirine. I have added a third photo where all of the less obvious species are labeled. The off-white plates are microcline, and all of the glassy stuff not labeled as nenadkevichite is natrolite. (The little colorless patches on the villiaumite are probably re-crystallized villiaumite – not more nenadkevichite.) Note that while the faces on the main villiaumite crystal are not smooth (due to etching and/or growth figures), they are nonetheless probably “real” faces – not cleavages.
The next pair of photos .5 x 2.4 mm) is a close-up of the main villiaumite crystal. It is essentially transparent.
The next photo (FOV 4.3 x 6.1 mm) is just a different view of the villiaumite (etc.). This is an older photo with somewhat oversaturated color.
The next photo (FOV 4.2 x 6.0 mm) shows the sérandite. It is of good size (4.2 mm) and color for the locality, but it is not well terminated (the “free” end is probably a contact). The crystal is surrounded by villiaumite cleavages.
Single item shipping weight is 3.2 oz (90 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 increases by about $0.20 per ounce. Above 13 oz, I will use Priority Mail (ca $9.25 including packing – varies by destination).
