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Ribbeite from
Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia
| Locality type: | Mine | |
| Classification | ||
|---|---|---|
| Species: | Ribbeite | |
| Formula: | Mn52+(SiO4)2(OH)2 | |
| Comments: | Ribbeite occurs as pinkish lenses up to 5 cm thick and 20 cm long, within a 20 m-wide zone of intercalated manganese and iron ores. The individual ribbeite grains are small, typically less than 0.5 mm, and often associated with other minerals. It has a preferential association with other Mn-bearing carbonates and silicates. Several parageneses are known, and the following is a description of the type specimen, as given by Peacor et al. (1987): “There are four distinct bands in the type specimen that seem to have been inherited from a sedimentary protolith, each dominated by different minerals. 1.) ...a 3 mm-wide band composed primarily of ribbeite and…subhedral pyrochroite…and a mcgovernite-like mineral. 2.) This grades moderately sharply into a 2 cm-wide band composed largely of ribbeite and chlorite, with minor spinels (jacobsite and galaxite) and calcite 3.) Manganoan calcite...intimately intergrown with ribbeite. The mcgovernite-like mineral occurs sparingly…The band containing ribbeite grades continuously into a 2 mm-wide band of manganoan calcite. 4.) The calcite unit in turn grades into a band consisting almost entirely of equigranular alleghanyite, but with some galaxite, jacobsite and calcite” Peacor et al. (1987) discuss the occurrence of both ribbeite and alleghanyite with almost identical compositon only millimeters apart, but within separate domains of the rock. | |
| Quality for species: | Excellent - world class for species or very significant. (!!) | |
| Confirmation | ||
| Validity: | Valid - Type Locality | |
| Associated Minerals Based on Photo Data: | ||
| Hausmannite | 1 | |
| Data | ||
| Mineral Data: | Click here to view Ribbeite data | |
| Locality Data: | Click here to view Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia | |
| Photo Gallery | View Gallery (3 photos) | |
| Data Identifiers | ||
| Mindat Occurrence Record ID: | 22800 | |
| Long-form Identifier: | 1:3:22800:4 | |
| GUID (UUID V4): | 0 | |
| References | ||
Peacor, Donald R., Dunn, Pete J., Su, Shu-Chun, Innes, John (1987) Ribbeite, a polymorph of alleghanyite and member of the leucophoenicite group from the Kombat mine, Namibia. American Mineralogist, 72 (1-2) 213-216 | ||
Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia