Description

CT opal specimen of the quincite variety, in association with sepiolite clay from its type locality, Quincy in the Cher department, France. Delivered with handwritten labels.

Quincite is found at the top of the Lacustrine Limestones of Berry, dated Middle Ludian to Upper Stampian (Upper Eocene – Oligocene). It is not a mineral species, but a variety of sepiolite (“clay”), colored by a pigment of organic (plant) origin, with the formula 2,8-Dipropylxanthenoxanthene-4,10-Quinone.

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