Naldrettite

Naldrettite
Naldrettite
General
Category Sulfide mineral
Chemical formula Pd2Sb
Strunz classification 02.AC.25d
Crystal symmetry Orthohombic
Unit cell a = 3.3906(1), b= 17.5551(5), c = 6.957(2) Å
Identification
Color Appears creamy white in plane-polarized light
Crystal system Orthorhombic
Twinning strain-induced polysynthetic
Fracture Irregular
Tenacity Ductile, Flexibly inelastic
Mohs scale hardness 4-5
Luster metallic
Diaphaneity opaque
Density 10.694(1) g/cm3
Refractive index in oil 1.515
Pleochroism non-pleochroic
Melting point 580 °C
References [1]

Naldrettite is a mineral with a chemical formula of Pd2Sb. It is named after Anthony J. Naldrett (b. 1933), a professor at the University of Toronto, who has made significant contributions to the International Mineralogical Association (IMA). Naldrettite is a new intermetallic mineral from the Mesamax Northwest deposit, Ungava region, Québec, Canada. Mineralization takes place around the base of basaltic dyke margins. Naldrettite is economically important because of its chemical composition (Pd2Sb). The sample in which the new mineral was discovered had high platinum group elements (PGEs) with palladium enrichment.[1]

Naldrettite occurs as anhedral grains that are commonly attached to sulfide minerals and are associated with clinochlore. It belongs to the orthorhombic crystal system and is a part of the pyramidal class.[1] This means that all of the edge lengths (a,b,c) of the unit cell are different in length and intersect at right angles to each other. The mineral is metallic, opaque, appears bright creamy white under plane polarized light, has weak bireflectance, and does not exhibit internal reflections.[2]

References

  1. ^ a b c Cabri,L.J., McDonald,A. M., Stanley, C. J., Rudashevsky, N. S., Poirier,G. Durham, B. R., Mungall, J. E., and Rudashevsky, V. N. (2005), Naldrettite, Mineralogical Magazine, 69, 89-97.
  2. ^ Mindat.org Accessed 28 October 2010