This specimen features very intriguing pseudomorphs of high  Mn siderite encrusted by tiny crystals of apatite (most likely fluorapatite). The siderite and apatite have been verified via EDS. (See the “Analysis” tab. On some specimens, the siderite is quite pink and may be Mn dominant – i.e. rhodochrosite.) The precursor is not known. Morphologically, the aggregates are reminiscent of nenadkevichite, lanthanite-(Ce), or perhaps petarisite or vuonnemie, but is hard to see how any of these could turn into siderite encrusted by apatite. However, it is very unlikely that the siderite is not pseudomorphous. Yet another example of the many perplexing pseudomorphs found at MSH. But note that these are “micro-pseudomorphs”. You will need about 15X to view them.

The specimen was found in July 1996, and is from a pegmatite that was very rich in clear, glassy, “jack-straw” elpidite, pink transparent albite, small “sunbursts” of aegirine, and small smoky quartz phantoms. Apart from minor (nearly colorless)  albite, and a few (non-phantom) quartz crystals, these  minerals are not evident on this small specimen.

The first pair of photos (FOV 2.2 x 2.6 mm), shows an aggregate of tabular pseudomorphs to about 1.4 mm on edge.

The second pair of photos (FOV 3.7 x 4.9) shows two similar aggregates.

Single item (small box) shipping weight 1.9 oz. For shipments outside the USA, up to a total weight of 8 oz (225 g), this could be combined with other items from this or future auctions for the same postage. If you wish to keep an “open box”, let me know.

For shipments within the USA, there is a nominal increase of about $0.20 for each additional ounce. Above 13 oz I will use “own box” Priority Mail ($8.75).