What is Calamaite?
Calamaite is a rare hydrated titanium sulfate, described from the Alcaparrosa Mine in Chile as colourless crystals and white aggregates.
Mineralogy and structure
The reference formula is Na2TiO(SO4)2·2H2O. Calamaite belongs to the sulfates and crystallises in the orthorhombic system. Calamaite has a new orthorhombic structure type and commonly forms acicular or hair-like crystals in radial clusters. Its hydration and good cleavage make dry, protected storage important.
Colour and appearance
Typical colours include colourless and white. For small or complex mineral species, crystal size, transparency, lustre and matrix association are often more diagnostic than colour alone.
Formation and localities
Calamaite forms in or is associated with strongly oxidised, sulfate-rich environments in arid mining districts. Important documented localities include Alcaparrosa Mine near Calama, Antofagasta, Chile. A precise mine or geological setting is preferable to a broad country label when it is known.
Collecting and care
Calamaite is best treated as a labelled reference or collector specimen. Protect fragile crystals from impact and humidity changes. Arsenic-, cadmium-, lead-, thorium- and selenium-bearing minerals should not be cut, ground or used in jewellery; wash hands after handling and keep them away from food and children.
