Zimbabweite

Zimbabweite is a mineral; formula (NaK)2PbAs(NbTaTi)O18. It is generally classed as an arsenite but is notable for also containing niobium  and tantalum. A yellow brown minral with orthorhombic crystal habit and a hardness of 5. It was discovered in 1986 in kaolinized pegmatite, i.e. weathered to clay, in Zimbabwe.
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General Information:
 Chemical Formula:
Na(Pb,Na,K)2(Ta,Nb,Ti)4As+++4O18
 Environment:
In a kaolinized pegmatite.
 IMA Status:
Approved IMA 1984
 Locality:
St. Ann's mine, Karoi district, SE of Miami, Zimbabwe.
 Name Origin:
Named for the country of origin.
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
yellow brown or honey yellow.
 Density:
6.2
 Diaphaniety:
Translucent
 Habits:
Euhedral Crystals - Occurs as well-formed crystals showing good external form., Tabular - Form dimensions are thin in one direction.,
 Hardness:
5-5.5 - Apatite-Knife Blade
 Luminescence:
Non-fluorescent.
 Luster:
Adamantine
 Streak:
white
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