Fribrous Calcite

This specimen is a well-developed example of fibrous calcite, displaying tightly packed, elongated crystal growth that produces a soft, silky lustre. The fibrous habit reflects rapid crystallisation under low-temperature hydrothermal or vein-related conditions, commonly associated with mineralised zones in Cornwall.

Historically, fibrous calcite was sometimes described using the term “satin spar” due to its lustrous appearance. In modern mineralogical usage, however, satin spar is now most commonly reserved for fibrous varieties of gypsum, and its application to calcite has largely been discontinued to avoid ambiguity. This specimen is therefore correctly identified as fibrous calcite, using precise contemporary terminology.

Cornwall is internationally significant for its long history of mining and mineral collecting, particularly during the 18th and 19th centuries. Provenance from the P. Cambridge Collection adds historical and curatorial value, reflecting the legacy of early British mineral collections and systematic study.

47 x 39 x 30mm

62g