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Formula: CaTe4+2Te6+O8
Tellurite
Crystal System: Monoclinic
Specific gravity: 6.3 measured, 5.7 calculated
Hardness: 3½
Streak: Very pale yellow
Colour: Yellow
Luminescence: No fluorescence under long wave or short wave UV
Environments
Localities
At the type locality, the Bambollita Mine, Moctezuma, Moctezuma Municipality, Sonora, Mexico, the altered wallrock
consists of granular quartz, some interstitial
sericite, and scattered white
dickite pseudomorphs after
sanidine. The ore veins carry
calcite and baryte as
gangue with scattered grains of
bornite, hessite and
galena.
Oxidation has produced fairly abundant bright yellow carlfriesite and colourful green crusts, which are a
mixture of an amorphous copper -
tellurium compound and dickite.
Less common are electrum, cerussite,
chlorargyite, and an orthorhombic
copper tellurite.
Carlfriesite occurs as botryoidal crusts lining cavities and less frequently as tiny sprays of sharply
euhedral crystals. It also commonly fills cleavage-plane fractures in the
baryte or occurs in tiny veinlets cutting the rock in the vicinity of
sulphide grains; rarely it is implanted directly on hessite or
bornite
(MM 40.127–130).
Carlfriesite from the Bambollita Mine -
Image
On the Upper dumps, North Star Mine, Mammoth, Tintic Mining District, Juab County, Utah, USA, carlfriesite is
extremely rare; however, nice, transparent, pale yellow euhedral crystals up to 1 mm have been found. Associated
minerals include goldfieldite,
pyrite, svanbergite,
utahite, xocolatlite,
xocomecatlite and zemannite,
on a matrix of quartz and baryte
(AM 55.2.187)>
Carlfriesite from the North Star Mine -
Image
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