Area: 0.3 hectares.
Geological Conservation Review site.
Description and Reasons for Notification:
A shallow circular pit exposes the central quartz felspar portion of a pegmatitic body once worked for lithium. The selvages of the pegmatitie are of biotite rock, with crystals up to 0.15m in length. Recent trenching to explore the pegmatite further, has cut through the biotite selvage which at this point is 2-3 m thick. Large lumps of solid biotite and coarse biotite pegmatite can be obtained from the working and the site is the best known locality for biotite mica in Britain. The pegmatite body is associated with the second intrusive phase of the Hercynian, St. Austell granite.