Safflorite

Safflorite is a rare cobalt iron arsenide with formula: (Co,Fe)As2. Pure safflorite would be just CoAs2, but iron is virtually always present. Safflorite is a member of the three-way substitution series of arsenides known as the löllingite or lollingite group. More than fifty percent iron makes the mineral lollingite whereas more than fifty percent nickel and the mineral is rammelsbergite. A parallel series of antimonide minerals exist.
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General Information:
 Chemical Formula:
(Co,Fe)As2
 Composition:
(Molecular Weight = 208.00 gm)
Iron 6.71 % Fe
Cobalt 21.25 % Co
Arsenic 72.04 % As
 Empirical Formula:
Co0.75Fe2+0.25As2
 Locality:
SOUT
 Name Origin:
From the German Safflor - "dyer's saffron."
Physical Properties:
 Cleavage:
[010] Imperfect
 Color:
gray, dark gray, or tin white.
 Density:
6.9 - 7.3, Average = 7.1
 Diaphaniety:
Opaque
 Habits:
Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Massive - Granular - Common texture observed in granite and other igneous rock.,
 Hardness:
4-5 - Fluorite-Apatite
 Luminescence:
None.
 Luster:
Metallic
 Streak:
grayish black
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