Naldrettite

IMA 2004-007

Naldrettit is a very rarely occurring mineral from the mineral class of sulfides and sulfosalts. It crystallizes in the orthorhombic crystal system with the chemical composition Pd2Sb (Chem. Palladiumantimonid, a compound of palladium (Pd), and antimony (Sb) ), and forms anhedrale grains of up to 240 micron size of creamy white color.

Etymology and history

The mineral was found in 2005 by LJ Cabri, AM McDonald, CJ Stanley, NS Rudashevsky, G. Poirier, BR Durham, JE Mungall and VN Rudashevsky in the type locality Mesamax on the Ungava Peninsula in the Canadian province of Québec.

Classification

In the classification by Strunz Naldrettit is counted among the alloys and alloy- like compounds, a subset of the sulfides and sulfosalts. After the 8th edition forms together with Cabriit, Paolovit, Taimyrit and Tatyanait a group of metals, alloys and intermetallic compounds, which belong to the mineral class of elements. In the 9th edition it forms with Majakit, Palladoarsenid, Palladobismutoarsenid, Palladodymit and Rhodarsenid a sub-group of compounds of semi-metals with platinum - group elements (PGE ), which are classified in the sulfides and sulfosalts.

In the classification by Dana, it forms a separate subgroup of the sulfides, selenides and tellurides with the composition AmBn Xp, with (m n): p = 2:1.

Education and Locations

Naldrettit is associated with pyrrhotite, pentlandite, chalcopyrite, galena, sphalerite, cobaltite, clinochlore, magnetite, Sudburyite, electrum and Altait.

From the very rare mineral finds are so far known only from the type locality.

Crystal structure

Naldrettit crystallizes in the orthorhombic crystal system, space group Cmc21 ( Raumgruppen-Nr. 36) with the lattice parameters a = 3.3906 Å, b = 17.5551 Å and c = 6.957 Å, and eight formula units per unit cell.