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MINERAL SPECIMENS FOR DISPLAY


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= Fluorescent Specimen
   =  Radioactive Specimen
  

 

BISMUTHINITE, FERBERITE, JAMESONITE, QUARTZ, PYRITE, ARSENOPYRITE
Rosario Adit, Tazna-Rosario Mine, Cerro Tazna, Potosi, Bolivia

Very unusual for the locality, this large cabinet specimen displays well developed, metallic gray Bismuthinite crystal prisms associated with tabular, dark brown-black Ferberite crystals.  Both minerals are mined at Tazna, but they are normally found in different veins or different levels in the mine, not often seen together on the same specimen.  Jamesonite is present as a secondary deposition, as tiny metallic gray needles coating some of the Bismuthinite crystals.  Identification of all three minerals has been confirmed by XRD.  Numerous small groups of colorless needle Quartz crystals are associated.  This is a museum quality specimen for any collection featuring ore minerals, or large display quality specimens.  The size of the largest Bismuthinite crystals average ~ 1 1/2 in length.  The largest Ferberite crystals are 1 to 1 1/4 across.  There are at least 7 half spheroids, up to about 3/8 across, of an unknown mineral on the base and perimeter of the specimen.  Some are shiny, and some are metallic gray, like they are coated with another mineral.  They are probably Pyrite.   Bolivians call this hemispheroidal type of Pyrite "melnikovita" (Melnikovite), which is a mixture of Pyrite and Marcasite. A couple of these metallic gray half spheroids can be seen in the upper left corner of the specimen, as oriented in the accompanying photograph.  Druses of very sharp Arsenopyrite crystals are also present around the perimeter of the specimen.

Specimen size:   7 X 4 1/2 across, X up to 4 1/2 thick
Order Item No.:  2968
Price:   $1,250.

Note:  This photo does not do the specimen justice!
BARYTE, PYROLUSITE

Haiti Mine, Cabezo de San Gines, Cartagena, Murcia, Spain
The Haiti Mine is a well known Spanish source for attractive, well formed specimens of crystallized Baryte and Calcite, associated with various manganese oxide minerals.  On this specimen, the entire top of the dome shaped, crystallized Baryte matrix is profusely covered with more than 100 sharp, lustrous, transparent, very pale smoky gray to colorless Baryte crystals averaging up to 1/2 and 5/8 in length.  Many of the Baryte crystals exhibit pronounced, sharp black Pyrolusite phantoms near the terminations.  This very nice display specimen is actually a large cast after an unknown mineral, that is, the back of the specimen is hollow, and the inside of the cast is also lined with small Baryte crystals (no rock matrix). 

Specimen size:  4 X 2 7/8 across X 2 thick
Order Item No. 2969
Price:  $125.

 

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