Main vein of Huelgoat district.
NS, 1100 meters long and 3 meters thick quartz vein in basal Dinantian volcanic formations, near Huelgoat granite.
Huge gossan rich in silver.
Ref.: Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 1012.
