Ardennite-(As) from
Torr Works Quarry, Cranmore, Mendip, Somerset, England, UK
Locality type: | Quarry | |||||||||||
Classification | ||||||||||||
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Species: | Ardennite-(As) | |||||||||||
Formula: | Mn42+Al4(AlMg)(AsO4)(SiO4)2(Si3O10)(OH)6 | |||||||||||
Comments: | Two specimens of Ardennite were found in 1977 by Chris Parkinson in blocks of loose vein quartz near the #1 and #2 veins. Although written up at the time by Bob Symes the paper was never published. Visually very similar to Salmchâteau material, the chemistry is quite different, being As-rich and V-poor. Turner and Rumsey (2010) found that these specimens of ardennite are chemically almost identical to some material from Salmchâteau. The difference in chemistry originally considered diagnostic happened because the specimen (from S-C) with which the 'Merehead' material was originally compared was found on re-examination to really be ardennite-(V), a species not described at the time of the original comparison. They also found doubts about the provenance of the material, including a ten-year gap between the stated 1977 date of finding and submission of the material to the NHM. The specimens are quite unlike anything else found at Merehead (and in the Mendips in general). More investigation is needed, but unless this mineral is found again in situ, it's occurrence at Merehead must be regarded as highly doubtful. | |||||||||||
Habit: | aggregates of honey-yellow prismatic crystals in vein quartz. | |||||||||||
Colour: | lemon to honey yellow, sometimes appearing mid-brown due to oxide coatings | |||||||||||
Luminescent properties: | n/a | |||||||||||
Abundance at site: | Very Rare | |||||||||||
Confirmation | ||||||||||||
Validity: | Erroneously Reported | |||||||||||
Data | ||||||||||||
Mineral Data: | Click here to view Ardennite-(As) data | |||||||||||
Locality Data: | Click here to view Torr Works Quarry, Cranmore, Mendip, Somerset, England, UK | |||||||||||
Data Identifiers | ||||||||||||
Mindat Occurrence Record ID: | 388849 | |||||||||||
Long-form Identifier: | 1:3:388849:0 | |||||||||||
GUID (UUID V4): | 4a2272cd-4c19-4626-952e-d6ae86e5fd90 | |||||||||||
References | ||||||||||||
Embrey, Peter G. (1978) Fourth supplementary list of British minerals. Mineralogical Magazine, 42 (322) 169-177 doi:10.1180/minmag.1978.042.322.01 | ||||||||||||
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