‘Plumbogummite’ from Roughten Gill, Cumberland

E. B. Förtsch
Department of Geology, University of Pretoria, R.S.A.

Summary: X-ray, infra-red, and optical studies suggest that the bluish-grey crust (previously described as plumbogummite) on arsenian pyromorphite from Roughten Gill, Cumberland, is a carbonate-bearing mix-crystal of plumbogummite, hinsdalite, and hidalgoite with a 7·018 Å, c 16·784 Å; arh 6·907, a 61° 3′; ω 1·680, ɛ 1·698.

Mineralogical Magazine; December 1967 v. 36; no. 280; p. 530-538; DOI: 10.1180/minmag.1967.036.280.07
© 1967, The Mineralogical Society
Mineralogical Society (www.minersoc.org)