Virtual Museum ID: 17-PME2724
Dolomite is an anhydrous carbonate mineral composed of calcium magnesium carbonate. The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite. An alternative name sometimes used for the dolomitic rock type is dolostone.
The information listed below relates to the current holding location or collection that the sample is from, and whether the item is viewable at that location or is part of a private collection. Coordinates are given as guides, and we remind you that collecting specimens from these locations is not allowed. Caution is advised visiting such sites and Below BC assumes no responsibility for any injuries or trespassing charges that may occur as a result of the viewer entering these sites.
Original Collection:Pacific Museum of Earth (PME)
Virtual Museum ID:17-PME2724
Date Added to VM:2017-12-08
Sample Origin:Quatsino, British Columbia
Specific Site:June Claims
Datum:09 (NAD 83)
Primary Mineral Formula:CaMg(CO₃)₂
Advanced Geological Information
The following section provides geological data relating to the specimen or the site it was collected from, when available. Information has been obtained from various sources including private and government datasets but may not be up to date. Any geological time periods or ages listed often relate to the primary geology of the area, and may not be the actual date of an event such as mineral formation.
Geological Formation:Vancouver Group(Quatsino Formation)
Geological Period:Upper Triassic
Stratigraphic Age:145 to 163.5 Million Years Ago
Geological Terrane:Wrangell, Plutonic Rocks
Minfile ID:092L 056
The June (L.180) occurrence is located is located north of June Creek, approximately 600 metres north west of the creek mouth on the Marble River.
The area is underlain by Upper Triassic Vancouver Group rocks comprised mainly of Quatsino Formation limestone and overlying volcanics and sediments of the Parson Bay Formation (Geological Survey of Canada Map 4-1974). The Vancouver Group rocks are intruded by granodiorite of the Late Jurassic Island Plutonic Suite.
At the June occurrence, Upper Triassic Quatsino limestone is interbedded with andesite flows and fine-grained tuffs of the Parson Bay Formation. The bedded rocks strike northwest and dip to the southwest at low angles. These rocks are in contact with an early intrusive phase consisting of dikes, sills and stocks of dark green hornblende diorite, and later phase felsic intrusive rocks, consist- ing of fine-grained granodiorite to light grey or white feldspar porphyry and aplite. The intrusive rocks are related to the Late Jurassic Island Plutonic Suite.
Limestone and volcanics near the intrusive contact have been epidote-chlorite-garnet-tremolite and actinolite altered. Mineralization consists of magnetite replacing hornblende diorite dikes and irregular replacement lenses, and small masses and disseminations of magnetite in granodiorite. Veins of quartz, magnetite, chalcopyrite and bornite are present. A skarn zone comprised of a 10 metre long, 15 to 45 centimetre thick sub-horizontal band of magnetite-garnet- pyrite-pyrrhotite was intersected in the main drift.
Mineralization on surface has been traced for 600 metres along the northwest striking contact. Unspecified mineralization is reported to the southeast on the Helen claim, Lot 181 (Assessment Report 502). Mineralization on Olga claim (Lot 183) and Minerva Fraction (Lot 171) are approximately on strike with the June occurrence.
A grab sample "from a trench near the June #2 post" assayed gold and silver trace, 59.4 per cent iron and 14.0 per cent sulphur (Minister of Mines Annual Report 1916, page K342).
A 45 tonne shipment of ore in 1907 assayed 5.95 per cent copper, 4.14 grams per tonne gold and 86.47 grams per tonne silver (Minister of Mines Annual Report 1907, page L151).
An assay plan, dated 1929, reports that diamond drill hole No.6 intersected four consecutive sections from 55.95 to 60.3 metres which averaged 7.2 grams per tonne gold, 16.5 grams per tonne silver and 0.94 per cent copper (Assessment Report 18812).
In 1987, a sample from the June crown grant assayed 0.5 grams per tonne gold, 17.5 grams per tonne silver and 1.35 per cent copper (Assessment Report 18812).
The June Group was originally staked in 1899 and optioned to Copper Mountain Mining who carried out a program of surface trenching in 1903. In 1916, an adit, 135 metres long, had been driven. During 1928 through 1932, Coast Coper completed 1350 metres of diamond drilling, 192 metres of drifting and 154.8 metres of cross-cutting. In 1963, Consolidated Exploration completed a program of soil sampling, geological mapping and a ground magnetometer survey on the area. In 1968, Alice Lake Mines completed a program of airborne geophysical surveys on the area. In 1989 and 1990, Equinox Resources, on behalf of Alice Lake Mines, completed programs of geochemical sampling on the area.