Images
Formula: V3+8Fe3+2O14(OH)2
Oxide of vanadium and ferric iron,
nolanite group,
nolanite supergroup
Crystal System: Hexagonal
Specific gravity: 4.65 measured, 4.60 calculated
Hardness: 5 to 5½
Streak: Brownish black
Colour: Black when massive, brownish black when powdered
Luminescence: No cathode luminescence under high-energy electron bombardment (30 KV)
Solubility: Soluble in sulphuric acid
Magnetism: Strongly magnetic
Environments
Localities
At the Kalgoorlie Consolidated Gold Mines, Kalgoorlie-Boulder, Kalgoorlie-Boulder Shire, Western Australia, Australia,
Nolanite is closely associated with massive native gold and numerous
telluride minerals (calaverite,
krennerite, petzite,
coloradoite, altaite and
sylvanite) in highly altered and metamorphosed
greenstones. No sulphide minerals were recognized in samples
containing nolanite, although minerals identified from the 865-foot level, South Kalgoorlie mine, include the
sulphides pyrite, chalcopyrite,
sphalerite and
tennantite-tetrahedrite, as
well as native gold, calcite,
dolomite and quartz, and the
tellurides calaverite,
krennerite, petzite,
coloradoite, altaite and
sylvanite.
Nolanite is confined to and localised in the greenstones
along the margins of small fractures. In some areas, fragments of shattered
greenstones containing nolanite grains are isolated in the
fissures. Nolanite formed early in the paragenesis before the late fracturing and subsequent massive flood of
precious metal mineralisation.
Nolanite occurs in subhedral to euhedral tabular prismatic grains from 10 to 50 microns in width and up to
several hundred microns in length. It is opaque, brownish black in powder, and submetallic in lustre. Nolanite
at Kalgoorlie apparently formed under relatively strong and uniform oxidising conditions
(AM 52.734-743).
As well as gold and gold
tellurides, associated minerals include
vanadium-bearing muscovite,
tourmaline, tivanite,
vanadium-bearing hematite and
vanadium-bearing magnetite
(HOM).
There are three co-type localities: the Eldorado Mining & Refining Ltd. mines, Beaverlodge Lake area, Saskatchewan,
Canada, the Ace deposit, Eldorado Mining & Refining Ltd. mines, Beaverlodge Lake area, Saskatchewan, Canada, and
the Nicholson No. 2, Consolidated Nicholson Mines, Goldfields District, Beaverlodge Lake area, Saskatchewan, Canada.
Other localities for nolanite in the Beaverlodge Lake Area include the Fish Hook Bay Mine and the Piche Group.
At the Beaverlodge Lake area, all the deposits containing nolanite are thought to be hydrothermal in origin.
The typical occurrence of nolanite is as concentrations of discrete subhedral to euhedral hexagonal plates from
10 to 20 microns across. Locally these plates have coalesced into massive material containing residual inclusions. In
the dolomite matrix of the Fish Hook Bay deposit, nolanite crystals
up to 1 mm across have been found. In leached zones some of these crystals have been freed by differential weathering
of the dolomite. In the Nicholson Mine, nolanite forms radiating
crusts on the dolomitised walls of the veins.
Pitchblende, calcite and sulphides
in turn form an inner layer toward the centre of the vein and fill interstices in the nolanite crust.
Minerals intimately associated with nolanite include dolomite,
quartz, calcite,
pyrite, hematite,
uraninite, chalcopyrite,
ilmenite and galena. Nolanite
fills cracks in euhedral pyrite but is mantled or cemented by massive
pyrite. It is also mantled by
chalcopyrite, pitchblende,
dolomite and quartz.
Hematite in part is veined by nolanite, but crystals of
hematite, together with crystals of nolanite, are embedded in
chalcopyrite and pyrite.
Ilmenite and nolanite in coalescing subhedral grains occur together,
cemented by quartz, calcite and
uraninite. In the Pitche group showing,
carnotite has been identified, presumably having been formed as a
weathering product of nolanite and uraninite
(AM 42.619-628).
Nolanite from the Fish Hook Bay Mine,
Beaverlodge Lake area - Image
Back to Minerals