The mine is also the type locality for the phosphates englishite, gordonite, millisite, montgomeryite, overite and wardite.
Larsen (1942b) made a detailed study of the paragenetic relationships in the evolution of variscite nodules in the Clay Canyon deposit, identifying six stages: (1) variscite formation, followed by fracturing and the introduction of thin black quartz veinlets; (2) banded minerals, primarily crandallite, millisite and wardite, replacing and enclosing variscite while opening up cavities through shrinkage (some variscite nodules were entirely replaced by crandallite); (3) formation of free-growing crystals of gordonite, englishite, montgomeryite and probably overite and kolbeckite in cavities; (4) a minor reversion to crandallite formation from solution as isolated oolites; (5) apatite-group minerals; and finally (6) the limonitic phase (limonite is not present inside any of the nodules).
Englishite [K.sub.3][Na.sub.2][Ca.sub.10][Al.sub.15][([PO.sub.4])sub.21][(OH)sub.7] * 26[H.sub.2]O
Englishite was described as a new species in the variscite nodules from the Clay Canyon deposit by Larsen and Shannon (1930), who named it after the prominent American mineral dealer George L.
Microcrystalline phosphate minerals, including carbonate-fluorapatite and englishite
, occur very rarely as late-stage products grown upon barite crystals from the 282-meter level.
Burangaite occurs as pale green radiating groups and hemispheres (to 0.3 mm) of simple prismatic monoclinic crystals, associated with englishite, carbonate-fluorapatite and variscite.
Englishite [K.sub.3][Na.sub.2][Ca.sub.10][Al.sub.15][([PO.sub.4]).sub.21] [(OH).sub.7] [multiplied by] 26[H.sub.2]O
The rare species englishite has been identified with other crystallized phosphates (burangaite, carbonate-fluorapatite and variscite) from unusual vugs at coordinates 17250N, 22000E on the 5,075 bench.