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Recently Released New Additions

Rare Minerals

Tuesday, 23 April 2024 06:00 PM

Introducing the "Rare Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including arsenopyrite, and gugiaite and more from places like Panasqueira, Covilha, Amazonas, Brazil, and Dugdu alkaline complex, Tuva, Siberia, Russia.

Arsenopyrite - BAC64023
Arsenopyrite - BAC64023

Arsenopyrite

with Pyrite - #BAC64023
Locality
Panasqueira, Covilha, Amazonas, Brazil 
Formula
FeAsS 
Availability
Available
Price
$25.00
Size
4.5 x 2 x 2.5 cm - Miniature 
Tagged
sulfide  

Bladed crystals of Arsenopyrite to 2cm long with a second generation of cockscomb habit Arsenopyrite. There are also numberous micro, cubic crystals of Pyrite.  It is quite interesting.


Arsenopyrite

Formula
FeAsS 
Crystal System
Monoclinic 
Crystal Habit
Striated, Euhedral Crystals, Prismatic 
Cleavage
one distinct 
Luster
Metallic 
Color
tin white, light steel gray 
Streak
black 
Geological Setting
Widespread. Most commonly found in medium to high temperature veins.  
Class
Monoclinic - Prismatic 
Fracture
Brittle 
Hardness
5.5 to 6 
Collection
William & Anne Cook Collection
Mineralpedia
View Arsenopyrite
On Dakota Matrix
Previously Sold Arsenopyrite
On Dakota Matrix
Other Available Arsenopyrite
WebMineral
View Arsenopyrite
Mindat
View Arsenopyrite
Gugiaite - 63676
Gugiaite - 63676

Gugiaite

#63676
Locality
Dugdu alkaline complex, Tuva, Siberia, Russia 
Formula
Ca2BeSi2O7 
Availability
Available
Price
$75.00
Size
0.3 x 0.2 x 0.2 cm - Thumbnail 
Tagged
beryllium  
Special Info
Type Locality 
Special Info
XRD Confirmed 

Light yellow plates of Gugiaite with dark purple Fluorite. Gugiaite is a rather rare beryllium silicate found in only five to six places in the world.


Gugiaite

Formula
Ca2BeSi2O7 
Crystal System
Tetragonal 
Cleavage
Perfect, Distinct, Indistinct 
Luster
Vitreous (Glassy) 
Color
colorless 
Streak
white 
Class
Tetragonal - Scalenohedral 
Fracture
Uneven 
Hardness
3-4 
Special Info
Type Locality
Special Info
XRD Confirmed
On Dakota Matrix
Previously Sold Gugiaite
On Dakota Matrix
Other Available Gugiaite
WebMineral
View Gugiaite
Mindat
View Gugiaite

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