Specimens of boracite from this English mine show a pale bluish tone, with complex forms of the tetrahedron, modified by the cube and the dodecahedron, and stepped growths. Between transparent to translucent. They are accompanied by colorless hexagonal tabular crystals of magnesite and aggregates of reddish-colored hilgardite crystals. Boracite shows reddish hues due to hilgardite inclusions.
Both boracite and hilgardite, are magnesium and calcium chloroborates respectively. This mine, which is located east of Loftus, near Easington, is worked to obtain sodium and potassium salts. When miners find veins of these borates, the rock becomes very hard, which is a problem for exploitation and a joy for collectors. This English mineral classics are not usual in the market.