MSH is the TL for donnayite-(Y). According to EDS (see the “Analysis” tab), the “donnayite” on this specimen has composition intermediate between donnayite-(Y) and mckelveyite-(Y). Both species are triclinic and, according to Igor Pekov, there is a complete series between them. Possibly one could interpret the scan as “high Ba donnayite-(Y)”, but comparison of peak heights in a “quick and dirty” EDS scan is risky. PXRD was also performed on a sample from this find, confirming “donnayite group” – but no more than that. Hence I have labeled the specimen “Intermediate donnayite-(Y)-mckelveyite-(Y)”.

This specimen is interesting because the “donnayite” fluoresces – something that has not been “officially” reported for any member of the group. The yellowish fluorescence isn’t very bright – but it’s clearly there. (However, this is hardly a fluorescent display specimen!)

In addition to the “donnayite”, there are a few small, but nice, crystals of “ilmenite-pyrophaniter series”. The material was not analyzed. In general, ilmenite and pyrophanite cannot be visually distinguished at MSH (unless the pyrophanite is clearly red).

The first photo (FOV 1.4 x 2.1 mm) shows one of the smaller “ilmenite “ crystals (p.7 mm) at top and one of the two “donnayite” aggregates (0.9 x 0.9 mm) at bottom.

The next pair of photos (FOV 2.35 x 3.6 mm) shows the largest “ilmenite (1.3 mm) at the top with the same “donnayite” aggregate at the bottom. The “ilmenite” sits on a nice transparent calcite crystal 1.8 mm in diameter.

The next pair of photos (FOV 3.2 x 6.15 mm) shows another donnayite crystal (or aggregate) 1.65 mm in maximum diameter, together with another calcite crystal. Everything sits on white analcime.

Single item shipping weight  is 2.8 oz. For shipments outside the USA, up to a total weight < 8 oz, 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).