Tunkwa Lake Hg Occurrence, Savona, Kamloops Mining Division, British Columbia, Canadai

Regional Level Types
Tunkwa Lake Hg Occurrence	Occurrence
Savona	Unincorporated Community
Kamloops Mining Division	Division
British Columbia	Province
Canada	Country

The Tunkwa Lake Hg occurrence is located immediately east of Tunkwa Provincial Park, about 16.5 kilometres south of Savona and 36 kilometres west of Kamloops, British Columbia.
There is a short description of the deposit and its history, on the British Columbia “Minfile” site, current to 2003, to which interested readers are referred. Relevant geological sections are quoted below:
“The Tunkwa Lake property is underlain by north striking and moderately east dipping Upper Triassic Nicola Group andesitic metavolcanics with intercalated siltstone, sandstone, argillite and occasional limestone units. The volcanics comprise andesitic agglomerates, and amygdaloidal and feldspar porphyry andesite flows. The Nicola rocks are locally cut by diorite dikes and later rhyodacite dikes. Several faults are believed to pass through the property. Wide zones of brecciated rock or gouge, pervasively carbonate and/or silica replaced, mark the trace of the larger faults on surface. Elevated mercury, antimony and arsenic values accompany late ankerite, dolomite and quartz veinlets and pervasive low temperature silica replacement to depths of at least 125 metres within one major fault zone, but precious metal values are uniformly low.
The most intense carbonate/silica alteration occurs at the Tunkwa Lake showing where the metavolcanics have been highly fractured and brecciated by a fault zone. A banded andesitic tuff is altered to ankerite and veined with dolomite. The carbonate zone is mineralized with disseminated stibnite, tetrahedrite, chalcopyrite, malachite and azurite with cinnabar occurring as thin films and small masses in dolomite and quartz veins. Zones of silica replacement occur up to 5 metres in width with several small silicified breccia zones mended with chalcedony.”
Information regarding mercury production from the property is sketchy. Cockfield (1961) reported that there was very minor production: “A retort had been erected in the property by the previous owners, but so far as is known there was no production. In the autumn of 1941 some prospecting was done on the property by D. B. Sterritt and associates of Kamloops. A total of just under 100 pounds of mercury was produced from a cut driven to the east of the shaft.” A photograph of the retort is presented in Stevenson (1940, Plate IV, p. 72). It is not clear from Cockfield’s report who in fact operated the retort and produced the mercury, or when.
Comments by Giles Peatfield on some of the minerals reported from the locality:
Arsenopyrite: Reported only by Johnson (1985), as “very rare”, in drill core.
Chalcedony: Reported by Morrison (1989), in drill cuttings.
Chalcopyrite: Johnson (1985) reported that “Only minor amounts of chalcopyrite were observed, usually in calcite veinlets in the relatively unaltered Nicola rocks.”
Graphite: Reported by Johnson (1985) in drill core.
Limonite: Reported only by Boyce (1981), but almost certainly just not mentioned by other workers.
One final point: Johnson (1985) mentioned that “Cinnabar, stibnite and realgar/orpiment are common throughout the main outcrop area surrounding the pond.” I have no idea what he was referring to when he wrote realgar/orpiment. Either one or both minerals would be possible, but there are no other data to support this.

Other Databases

Link to British Columbia Minfile:	092I 039

Other Regions, Features and Areas containing this locality

References