What is Wöhlerite?
Wöhlerite is a complex sodium calcium zirconium silicate of alkaline igneous rocks, valued for its unusual niobium-zirconium chemistry and warm colour.
Mineralogy and structure
Reference formula: Na2Ca4(Zr,Nb)2Si4O16(O,F,OH)2. Wöhlerite is monoclinic and compositionally variable, with Zr-Nb and O-F-OH substitutions. COD 9009530 is used as a labelled representative natural structure. Wöhlerite is classified with silicates and has monoclinic crystal symmetry. Typical hardness is 5–6 on the Mohs scale and specific gravity is approximately 3.2–3.5.
Colour, lustre and habit
Typical colours include yellow, brown, orange-brown, greenish, white. The usual prismatic, granular, massive habit and vitreous, resinous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Wöhlerite forms in or is associated with nepheline syenites, alkaline pegmatites and silica-undersaturated intrusive complexes. Important documented localities include Norway, Russia, Canada, Greenland and other alkaline-rock localities.
Complex rare-element chemistry in an alkaline rock
Wöhlerite is a specialist collector mineral whose appeal comes from the rare-element story: zirconium and niobium chemistry in a distinctive alkaline geological setting.
Collecting and care
Protect from acids and impact; retain the alkaline host-rock context and avoid presenting a variable composition as a fixed analysis.
