Specimen #2446

Name: Phosphosiderite

Type: Gem

Locality: Chile

Favorite? N

Fluorescent? N

Size: 16.22 mm x 12.23 mm

Weight: 8.49 ct

Acquired: 2012-06-14

Source: Arkenstone Auction

Label: N

Comment: Phosphosiderite is fairly uncommon hydrated iron phosphate that is rarely seen in the gem world. Recently, we obtained a small parcel of what are some of the richest Phosphosiderite gems with some of the richest color that I have seen for the material. Originally, we were told that the stones are from Sapucaia, Brazil, which has procuded massive Phosphosiderite in the past, but we now have both visual and verbal confirmation that these stones are actually coming out of Chile. I'm told that the reason for all the confusion as to the origin of this material may be the fact that the rough could lie in a National Park, where collecting is illegal, so the locals have done their best to use subterfuge. I was able to find a photo of the rough online on a Chilean gem exporter's website. http://www.chileangems.com/Rough%20chilean%20stones/fosfosiderita.jpg . Now that we know this material is both natural (we had this material analyzed, and it was verified as fine-grained Phosphosiderite. I am happy to provide a copy of the analysis to anybody who would like it), and its true origin, we feel 100% confident in offering it for sale. This gem has an "Oval Cabochon" cut with a very distinctive purple/lavender hue. The is solid Phosphosiderite, with no other minerals mixed in, which is rare in my experience. I have only seen a few very tiny faceted gems of this material in my life, but cabochons such as this one are rare and attractive, not to mention worthwhile for any gem collector.

Minerals: Pharmacosiderite (KFe⁺⁺⁺₄(AsO₄)₃(OH)_{4 6}^-₇(H₂O))

There is one picture on file

M02446-01.jpg:

Phosphosiderite, Chile - FOV: 12.5 x 18.8 mm - 53 stacked images