Pb-Zn-Ag ± Au

Virtual Museum ID: 19-MEM16

Specimen Summary


Galena is the main ore mineral for lead. Because of its relatively low melting temperature it can be easily smelted and has been used as a source of lead since ancient times. Galena has a cubic crystal system and can often be found as cubes or octahedra. Its shiny grey metallic lustre and heavy, dense nature make it easy to recognize. Galena often contains small amounts of silver, which add to its economic value.

Sphalerite is the main ore mineral for zinc, and although relatively common, finding it in commercial amounts is somewhat rarer. The zinc will give the mineral a yellow or red hue, but iron can replace the zinc in the atomic structure, making the crystals black. Rarely, cobalt finds its way into the structure, and produces green crystals.

Silver is an important precious metal. It is still highly valued today and has many important uses, as well as being used for jewellery. Silver has the highest electrical and thermal conductivity and reflectivity of all metals and is widely used in electronics and industrial chemistry. It is also used to make mirrors, photographic and x-ray film and collectible coins. Silver has natural antiseptic properties, therefore, has many different medical applications. Silver can occur in its elemental form as metallic silver, or in compounds and minerals with other elements like gold and lead. Silver has a distinct silver-grey colour and is soft and malleable, meaning it can be easily worked and shaped.

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. In its natural mineral form, gold is commonly alloyed with silver. Gold is distinguishable by its characteristic golden yellow colour and extreme heaviness.

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:

Ministry of Energy, Mines & Petroleum Resources of Cranbrook (MEM)

Sub Collection:

-

Collection ID:

MEM_16

Virtual Museum ID:

19-MEM16

Accessibility:

Date Added to VM:

2019-06-14

Location Information

Sample Origin:

Sandon, B.C.

Specific Site:

Wonderful Mine

UTM Easting:

482196

UTM Northing:

5536684

Datum:

11 (NAD 83)

Coordinate Accuracy:

Specimen Details

VM Category:

Rock

Primary Features:

Pb-Zn-Ag ± Au

Primary Mineral Formula:

Pb, Zn, Ag, Au

Primary Category:

native element

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:

Slocan Group

Geological Period:

Upper Triassic

Stratigraphic Age:

145 to 163.5 Million Years

Geological Belt:

Omineca

Geological Terrane:

Quesnel

Minfile ID:

082FNW043

Site Details:

The Wonderful occurrence is situated on Reverted Crown grant Lot 481 at 1280 metres elevation above sea level, on the south side of Carpenter Creek, in the Slocan Mining Division.

The Wonderful property 0.3 kilometre west of Sandon, was among the earliest locations in the area. Discovery of galena float led to ground sluicing operations in 1894 and the uncovering of a train of boulders of almost massive galena. This operation came to an end in 1896 after about 360 tonnes of ore had been recovered. Early underground development was unsatisfactory. The first workings were exploratory and apparently no definite lode was encountered. In 1915 the property was acquired by Clarence Cunningham and later, 1924, by Cunningham Mines Limited, which was responsible for most of the development on the property.

The Wonderful mine was opened by 2 levels, the "A" elevation 1282.5 metres, and the No. 1, elevation 1251.8 metres. The productive level "A" is connected by a raise with 6 interior levels at 30, 43, 61, 74, 90 and 127 metres above the adit level. Several small sub-levels were also established. These workings are now inaccessible. In 1948 the property was acquired by Silver Ridge Mining Company.

In 1948-49 an adit known as the Pearsons adit, located approximately 59 metres below "A" level and 29 metres below No. 1 level, was driven on a lode uncovered by stripping on the projection of the drift on No. 1 level. The lode was intersected 30.4 metres from the portal, and was followed to the west for 177 metres; a section of drift 42.6 metres long was detoured into the footwall to avoid bad ground.

Where first encountered the lode contained some sphalerite and galena. In 1951 a nearly vertical fissure was encountered 10.6 metres in the footwall at a point 79.2 metres west of the crosscut. In the first 30.4 metres of drift this fissure is mineralized erratically and contains as much as 0.9 metre of sphalerite, as well as local masses of galena.

The Lookout adit was started in 1946 at an elevation of 1300 metres, on the Lookout No. 2 claim. This adit was begun as a general exploratory tunnel, and was driven as a crosscut 686.4 metres at south 78 degrees west. At a point 365.7 metres from the portal a branch extends for 696.4 metres bearing about N 24 degrees W; the inner 91.4 metres of this branch is deflected nearly 200 degrees westerly. A zone consisting of 2 sub-parallel fissures 6 metres apart containing calcite and siderite was encountered about 495 metres northwest of the main crosscut.

An old adit on the Early Bird claim (082FNW229) at an elevation of about 1128 metres is entirely in quartz diorite. Workings here total about 122 metres.

A mineralized lode discovered in No. 2 ("A" adit?) was explored in 1952 by a new, No. 3 adit and a raise driven to connect the 2 levels. In the same year No. 4 adit was started and continued in 1953. About 305 metres from the portal a lode was intersected in the approximate projected position of the lode intersected in No. 3 adit. In the Period from 1953 to 1956 the property was idle except for exploratory work on a small scale. In 1956 a narrow vein was exposed by stripping close to 100 metres from the Pearson adit, and a new adit started on the showing. In 1958 this adit had reached a total length of 7.6 metres. In December of that year an agreement was entered into with Violamac Mines Limited for the development of the Silver Ridge properties. The only work recorded on this property since was the extending of the adit started in 1956, for an additional 17 metres. In 1979, G. Sipos shipped 120 tonnes from the property.

Regionally, the area lies on the western margin of the Kootenay Arc, in allochthonous rocks of the Quesnel Terrane. In the vicinity of the occurrence, the Quesnel Terrane is dominated by the Upper Triassic Slocan Group, a thick sequence of deformed and metamorphosed shale, argillite, siltstone, quartzite and minor limestone. Rocks of the Slocan Group are tightly and disharmonically folded. Early minor folds are tight to isoclinal with moderate east plunging, southeast inclined axial planes and younger folds are open, southwest plunging with subhorizontal axial planes. The sedimentary sequence has been regionally metamorphosed to lower greenschist facies.

South of the occurrence, the Slocan Group has been intruded by the Middle Jurassic Nelson intrusions which comprise at least six texturally and compositionally distinct phases ranging from diorite to lamprophyre. The most dominant phase is a medium to coarse grained potassium feldspar porphyritic granite. Several feldspar porphyritic granodiorite dikes, apparently related to the Nelson intrusions, also cut the sedimentary sequence near the occurrence (Paper 1989-5).

The Wonderful occurrence is hosted by argillite and slate of the Slocan Group. The rocks strike 165 degrees and dip 35 to 50 degrees northeast. The strata are believed to lie on the west limb of a syncline because the dip changes to southwest just east of the underground workings (Geological Survey of Canada Memoir 184). The sedimentary rocks are cut by joints that strike 060 degrees and dip steeply to the southeast. This orientation is similar to some mineralized veins exposed on the property. Several granodiorite and quartz monzonite dikes up to 15 metres wide cut the sedimentary sequence. The hostrocks are heavily pyritized close to the mineralized veins.

The Wonderful deposit occurs in a reverse sinistral (40 degrees east) fault zone that is cut and displaced by faults, subparallel to bedding, with generally sinistral but also dextral movements of up to 50 metres. The main orebody is developed be five main and three intermediate levels. The workings have a vertical range of about 180 metres below the surface. The main orebody strikes east and dips 50 to 90 degrees south. The ore occurs in a sheared and mineralized fracture that shows evidence of pre and postmineral displacement. The fissure vein is about 2 metres wide and consists of crushed wallrock cemented by quartz, calcite and siderite. The ore is brecciated and consists of fragments of galena, sphalerite and country rock with siderite. Pyrite and pyrrhotite are common and oxidation is pervasive. Minor tetrahedrite may also be present.

Past production between 1896 and 1979 yielded about 13 tonnes of silver, 1619 tonnes of lead, 1214 tonnes of zinc and 6 kilograms of gold from 28,806 tonnes mined.

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