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[Jesse Fisher]

"Black" fluorite from Frohnau. I have seen some of these specimens labeled as coming from "Zehnthausend Ritter Mine." This one was labeled "Bergmannisch Gluck Flacher, Wismut 29b Shaft." Are these the same location?

[Andreas Gerstenberg]

Hi Jesse,

the old name for the mine was Zehntausend Ritter, the WISMUT company in the 40s and 50s gave numbers to their shafts so 29b is the "WISMUT expression" for the Zehntausend Riitter mine. Bergmännisch Glück Flacher is the name of the vein these fluorites were found in. But you even see Bergmännisch Glück as the mine´s name (and i think there was a mine of that name in Frohnau). However, there were quite a number of mines in that area in the old days. All the colourful fluorites that come out from Frohnau in these days are from that very region - but sometimes it´s hard to say from which place in particular.

Cheers
Andreas

[Andreas Gerstenberg]

Three Saxonian classics recently added to my collection:

[Tobi]

Once again a fluorite from Saxony. This specimen once was in my collection, somehow I forgot to put it in this thread:

[Tobi]

Rather large and fine specimen of Germany's most prominent fluorapatite:

[Jesse Fisher]

Time for another fluorite from Saxony. An old specimen from Annaberg, likely 19th century, acquired at the recent Munich show. The specimen was featured in the Extra Lapis n. 4, "Fluorit" issue.

[Andreas Gerstenberg]

Rare piece indeed. Old, labelled Annaberg specimens don´t occur that often.

[Jesse Fisher]

Another recently acquired fluorite from Saxony. Associated minerals are quartz, barite and dolomite. The specimen came with an old hand-written label that reads "Flussspat, Freiberg in Sachsen." It looks very much like some specimens I have seen from Halsbrucke, but it came with no exact location information.

[Tobi]

[Jesse Fisher]

Hello Tobi, Thanks for the information. There is a small amount of what looks like fine grained galena in the quartz matrix, but no other sulfides. The back of the specimen is covered with small white sheaf-like crystal clusters of barite. I assume the specimen is an old one based on the old label. How old were either of these mines?

[Tobi]

Galena occured in both of these mines, so I don't know if this helps. The Grube Behilfe area was mined since 1600 and the mine closed in 1969, Grube Segen Gottes and its surroundings are assumed to be mined since the middle-ages, the mine was closed in 1885. I fear these information will also not be very helpful :-(

[Jesse Fisher]

This is the same problem with old English fluorite specimens, sometimes it is impossible to say exactly where they came from!

[Andreas Gerstenberg]

Hi Jesse,

although the Beihilfe mine is very old you won´t see any specimens dating before 1945. I think that your fluorite came from the Churprinz mine near Großschirma (also in the Halsbrücke part of the Freiberg mining district). The dolomite in the paragenesis speaks for Halsbrücke. Gersdorf produced many specimens with yellow cubes but i´ve never seen a single piece with dolomite crystals on.

Best regards
Andreas

[Thomas Uhlig]

I agree with Andreas. The dolomite in paragenesis with yellow Fluorite is a characteristic mineral association for the Halsbrücker Spat (vein).

Below is an example for an old Segen Gottes Mine Fluorite with crystals up to 7 cm associated with Barite and Chalcopyrite and some minor Calcite.

Another typical paragenesis for Segen Gottes Mine's Fluorites are small clear isolated Quartz crystals sitting on the yellow to orange Fluorite.

[Jesse Fisher]

The specimen definitely has what appears to be dolomite partially coating some of the fluorite crystals.