What is Cafetite?
Cafetite is a hydrated calcium titanate known for yellow to colourless acicular or radiating crystals in alkaline rocks.
Mineralogy and structure
The reference formula is CaTi2O5·H2O. Cafetite belongs to the oxides and crystallises in the monoclinic system. The monoclinic structure and revised formula distinguish cafetite from the historically confused mineral kassite. Mindat records columnar to acicular crystals and radiating aggregates, which should be protected from abrasion.
Colour and appearance
Typical colours include yellow and colourless. For small or complex mineral species, crystal size, transparency, lustre and matrix association are often more diagnostic than colour alone.
Formation and localities
Cafetite forms in or is associated with alkaline and ultrabasic rocks, cavities and titanate-rich mineral assemblages. Important documented localities include the Afrikanda massif on the Kola Peninsula, Italy and other alkaline complexes. A precise mine or geological setting is preferable to a broad country label when it is known.
Collecting and care
Cafetite 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.
