Witherite with Baryte

Hemispheres of Witherite measuring to over 2 cm are formed on a dark grey Limestone matrix from Nentsberry Haggs mine at Alston in east Cumbria. The Witherite, a rare barium carbonate, is coated by a crystalline druse of white secondary Baryte.  The type locality for Witherite is the nearby Brownly Hill mine, just to the other side of the town of Alston.  The rare carbonate minerals from this area often don’t stand out due to their more subtle colours of off-white and cream, but form an important suit well known for their simple yet unusual chemistry.