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135 mm Thomsonite

$ 69.99



Bumannsfjorden, Seiland, Finnmark, Norway

Size: 100x135x140 mm (1963 grams)


Rare light pink Thomsonite pseudomorph after Nepheline, combined with cola-brown Grossular on white Calcite.

It is a very rare combination, and my father found just a few ones like this. I have now got it proven by lab that it is in fact Thomsonite. You can also see the mineral listed at Seiland at Mindat:

In mineralogy, a pseudomorph is a mineral or mineral compound that appears in an atypical form (crystal system), resulting from a substitution process in which the appearance and dimensions remain constant, but the original mineral is replaced by another.

This specimen is a huge crystallized Thomsonite.
The Thomsonite is "knocked off" on the sides and back, plus a flake of the crystal gone in the front.

In addition you can see brown Grossular that are partly weathered.

Bumannsfjorden, Seiland, Finnmark, Norway

Most of the year the field where the minerals are found is covered with ice and snow, and today this area is now a part of the Seiland National Park, and collecting from this area is now strictly forbidden. So not only is this a rare material but also it will not be collected more of it.

This specimen was found in the late 1980's by my father, Gunnar Mathisen. 

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