Leucophoenicite

Leucophoenicite
Leucophoenicite from the Wessels Mine in Kuruman, South Africa.
General
CategoryNesosilicates
FormulaMn7(SiO4)3(OH)2
IMA symbolLpo
Strunz classification9.AF.60
Dana classification52.3.2c.2
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/a
Unit cella = 10.84 Å
b = 4.82 Å
c = 11.32 Å
β = 103.93°; Z = 2
Identification
CleavageImperfect on {001}
TenacityBrittle
Mohs scale hardness5.5 to 6
LusterVitreous
DiaphaneityTransparent to translucent
Optical propertiesBiaxial (−)
Refractive indexnα = 1.751
nβ = 1.771
nγ = 1.782
Birefringenceδ = 0.031
PleochroismFaint; rose-red {001}
Colorless {001}
2V angle74° (measured)
Ultraviolet fluorescenceNon-fluorescent
References

Leucophoenicite is a mineral with formula Mn7(SiO4)3(OH)2. Generally brown to red or pink in color, the mineral gets its name from the Greek words meaning "pale purple-red". Leucophoenicite was discovered in New Jersey, US and identified as a new mineral in 1899.