Gold chalcopyrite

Virtual Museum ID: 19-DV11

Specimen Summary


Gold is a valuable, highly prized mineral used in everything from jewellery to electronics and dentistry. Gold is desirable due to its special properties, such as malleability and resistance to tarnishing. Gold is commonly microscopic or embedded within or around sulphide grains. Free visible gold occurs as disseminated grains, or rarely as crystals. Crystals of gold commonly form within or around quartz. In its natural mineral form, gold is commonly alloyed with silver. Gold is distinguishable by its characteristic golden yellow colour and extreme heaviness.

Chalcopyrite is an important copper ore mineral found in many different types of copper deposit. It is sometimes mistaken for Gold because of its bright yellow colour; however, it is harder, more common, and chalcopyrite commonly occurs with other copper sulphide minerals such as bornite and weathers to malachite and azurite.

Specimen Data

 

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.

Collection Details

Original Collection:

Drifter Ventures Ltd. (DV)

Sub Collection:

-

Collection ID:

DV-11

Virtual Museum ID:

19-DV11

Accessibility:

Date Added to VM:

2019-08-15

Location Information

Sample Origin:

Smithers, BC

Specific Site:

Dome Mountain

UTM Easting:

653141

UTM Northing:

6068487

Datum:

09 (NAD 83)

Coordinate Accuracy:

Specimen Details

VM Category:

Mineral

Primary Features:

Gold chalcopyrite

Primary Mineral Formula:

Au, CuFeS2

Primary Category:

native element sulphide

Secondary Features:

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:

Nilkitkwa Formation (Hazelton Group)

Geological Period:

Lower-Middle Jurassic

Stratigraphic Age:

201.3 - 163.5 Million Years Ago

Geological Belt:

Intermontane

Geological Terrane:

Stikine

Minfile ID:

093L 022

Site Details:

At the Dome Mountain (Forks) occurrence, the original showing was in the creek bed, in a northeast trending shear zone in schistose andesites of the Lower-Middle Jurassic Nilkitkwa Formation (Hazelton Group).

The Forks consists of two veins that are found to be striking west south/west and dipping at a shallow angle towards the Boulder structure. The Forks Gold Deposit is a flat lying, extremely sheared and altered quartz breccia vein structure with a thickness of up to 12 metres. Drilling in 1987 intersected intervals up to 7.6 metres grading 10.42 grams per tonne gold and 53.38 grams per tonne silver (as reported in Assessment Report Assessment Report 28891).

The orebody (10 by 30 metres long) was reported as quartz heavily charged (5 to 10 per cent) with galena, arsenopyrite, pyrite and sphalerite. Later tunnelling outlined two quartz veins averaging 30 to 150 centimetres in width hosted in sericite-carbonate-fuchsite altered and foliated tuffs. The veins contain pyrite, galena, sphalerite and arsenopyrite. One vein, trending northwest and dipping northeast averages (weighted) 42.1 grams per tonne gold and 85.4 grams per tonne silver over 12 metres. The other vein trends northeast and averages 15.3 grams per tonne gold and 59.0 grams per tonne silver.

Prospectors first staked claims on Dome Mountain in 1914 to cover several showings of gold-bearing quartz veins. In 1923, three shafts, totalling 225 metres of underground drifting were completed on the property by Dome Mountain Mining Company. The next year, all work was halted due to the patchy nature of the gold mineralization and excessive water in the workings.

Noranda Exploration Corporation Limited consolidated all the claims on Dome Mountain in 1984 and conducted a program of soil geochemistry surveys, geological mapping, trenching and 33 diamond-drill holes. Canadian-United took over the operation in 1985 and proceeded with a diamond drilling program.

In 1989, Teeshin Resources Limited reported mineable reserves of 18120 tonnes at 23.67 grams per tonne gold from a shallowly dipping vein in the Forks zone (Property File Placer Dome Smit., 1990).

Drilling in 1985 defined a geological reserve of 20,000 tonnes grading 23.6 grams per tonne gold (Fieldwork 1986, page 212).

WORK HISTORY

Production is given for 1940 and 1951 totalling 5 tonnes but historic records do indicated work being done on Dome Mountain at that time.

In the early 1920s, on the Forks showing a shaft was sunk to 32.6 metres, a crosscut was driven to the vein on the 30 metre level, and "several hundred feet" of drifting carried out.

Work in 1985, with Noranda as operator, included trenching, and 1564 metres of diamond drilling in 33 holes on the Forks showing (093L 022); this work indicated 91,000 tonnes at 19.2 grams per tonne gold (George Cross News Letter, 1985, No. 240). However Assessment Report 28891 gives the following statement, "From 1985 to 1987 a total of 23 diamond drill holes on the Forks Gold deposit outlined a resource of 20,000 tonnes at a grade of 23.6 grams per tonne gold." The resource values in this paragraph appear to be at odds.

In 2008, Eagle Peak Resources collected soil sampling over a grid that covered Dome Mountain (Boulder) (093L 276), Forks (093L 022) and 9800 (093L 277). An IP survey was conducted over 22 kilometres and ground magnetic survey over 23.1 kilometres.

Refer to Dome Mountain (Boulder vein) (093L 276) for related details and a complete Dome Mountain property work history.

Additional Images