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MINERAL SPECIMENS FOR DISPLAY


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= Fluorescent Specimen
   =  Radioactive Specimen
 

ACANTHITE pseudo after ARGENTITE
Mina General, Municipio de Fresnillo, State of Zacatecas, Mexico
Two upright, intergrown aggregates composed of shiny black Acanthite after Argentite crystals are standing up from a crystalline Acanthite base.  No rock matrix or point of attachment.  Attractive!  Lorraine Sofia collection.
Specimen size:  1 1/4” tall, 1” wide, 3/4” thick
Specimen weight:   10.85 grams
Price:  $325.00 SOLD
Order Item:  MI-1501

 


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COPPER, MALACHITE, DOLOMITE
Tsumeb, Namibia
Native Copper is fairly common at Tsumeb, being one of the ore minerals, however, it is decidedly rare in good specimens.  This specimen is an arborescent “tree”, with the branches standing out in tree-like fashion.  The Copper is oxidized, i.e., in natural condition, never cleaned.  The specimen has a secondary deposition of many hundreds of tiny “dew drops” of slightly curved, micro, translucent-white Dolomite crystals (up to 1 mm size) richly sprinkled over many surfaces of the specimen. On one side, a patina of secondary Malachite has begun to form.  No rock matrix.
Specimen size:  2 1/2” tall, and 1 1/2” X 1 1/4” in cross section
Order Item MI-1186              Price:  $125.00



 

SCHORL TOURMALINE with MUSCOVITE
Itinga, State of Minas Gerais, Brazil
This attractive specimen has a large, double terminated, shiny black Schorl crystal 2 1/4” in length X 7/8” in cross section, with a very interesting multi-faced termination on one end and a matte luster termination on the other end.  The Schorl crystal is perched upon a cluster of several intergrown, smoky gray, hexagonal Muscovite crystals.  The largest Muscovite crystal is 1” X 1/2” across, and 1/2” thick.  No rock matrix.  Lorraine Sofia collection. 
Specimen size:  2 1/4” (the length of the Schorl crystal, X 1 3/4” X 1 1/4”
Order Item MI-1161  Price: 
SOLD


MI1 497 Front

MI 1497 Back

ACANTHITE pseudo after ARGENTITE
San Juan de Rayas Mine, Guanajuato, Mexico
Both specimens pictured at the left are composed of very shiny, metallic black Acanthite (pseudomorph after crystallized Argentite).  Each specimen has formed as a free-standing intergrowth composed of many stacked, cubic crystals without matrix or point of attachment.  Acanthite is a silver sulfide:  Ag2S

MI-1497   The largest, slightly elongated cubic crystal at the top of this specimen measures 10 mm tall X 6 mm wide.  F. Marshall collection.
Specimen size: 1 1/2" tall, 3/8" wide, 1/4" thick.
Specimen weight:  4.00 grams
Price: $250.

MI-1498  This exceptional specimen consists of an elongated, stacked, very “hefty” intergrowth composed of more than 20 cubic and modified cubic crystals, without matrix.  The largest modified cubic crystal at the top of the specimen is 11 mm tall X 8 mm wide.  The base of the specimen is also terminated, though slightly crudely developed.  Lorraine Sofia collection.
Specimen size:  1 1/2” tall, 3/8” wide 3/8” thick.
Specimen weight:  9.62 grams
Price:  $400.


MI 1498 Front

MI 1498 Back
COPPER
Keweenaw Peninsula, Michigan
Bright native Copper has formed numerous sharp crystals in an arborescent grouping, without rock matrix. The largest crystals on the specimen measure 3/8", and 1/2" in length. Very minor bits of white Quartz are associated, otherwise, there is no rock matrix. This specimen is in natural condition, not acid etched.
Size: 2 3/8" tall X 3/4" wide X 1/2" thick.
Order Item MI-015 Price: $250.

 

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