Tsumebite from
Roughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
| Locality type: | Mine | |
| Classification | ||
|---|---|---|
| Species: | Tsumebite | |
| Formula: | Pb2Cu(PO4)(SO4)(OH) | |
| Comments: | Cooper & Stanley (1990): "An arsenatian tsumebite was recorded by Embrey (1977) from 'Carrock Fell', but the collector of the material subsequently reported the locality more precisely at Roughton Gill at [NY302343]; i.e. between the 60 and 90fm level (Moffit, 1979). The authors have found tsumebite to be an occasional associate of brochantite in specimens collected from the main dumps of Roughton Gill. It forms tiny (c. 0.25mm) pale apple green drusy aggregates and rarely scaly crystals on compact quartz. Associated brochantite crystals reach 2-3mm and cerussite is occasionally present. First identified on a specimen collected by D.R. Middleton (det. BM(NH): XRD; University of Manchester Institute of Science and Technology (UMIST): IR." Bridges et al. (2011): "Small (c. 0.25 mm) apple green drusy crystals of ‘tsumebite’ in association with brochantite were noted by Cooper and Stanley (1990). It remains an uncommon mineral but has been found in the current study as crusts of similar sized crystals, again associated with brochantite. Tindle et al. (2006) analysed four ‘tsumebite aggregates’ and showed the presence of arsenic in all of them. The arsenic becomes richer towards the outside of the crystals and in one case, at the outer edge of the AsO4/PO4 site, is 53 mol% AsO4 and just falls within the arsentsumebite field." | |
| Habit: | drusy aggregates; scaly crystals | |
| Colour: | apple green | |
| Confirmation | ||
| Validity: | Confirmed | |
| Confirmation Methods: | XRD Infrared Spectroscopy | |
| Associated Minerals Based on Photo Data: | ||
| Brochantite | 2 | |
| Pyromorphite | 1 | |
| Quartz | 1 | |
| Data | ||
| Mineral Data: | Click here to view Tsumebite data | |
| Locality Data: | Click here to view Roughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK | |
| Photo Gallery | View Gallery (2 photos) | |
| Data Identifiers | ||
| Mindat Occurrence Record ID: | 11256 | |
| Long-form Identifier: | 1:3:11256:3 | |
| GUID (UUID V4): | 0 | |
| References | ||
Roughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK