Au in quartz from granite
Virtual Museum ID: 19-NCM15
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.
Quartz is the second most abundant mineral on Earth, present in many different types of rocks. Although usually clear or milky white in colour, quartz is found in a variety of colours due to impurities in the crystal structure. Pure quartz consists of silicon and oxygen only, but atoms of other elements often make their way into the quartz crystal structure, colouring the crystals. Some varieties of quartz, like purple amethyst and yellow citrine, are considered to be semi-precious gemstones and have been used since ancient times to make jewellery and decorative objects. Well-formed (euhedral) crystals of quartz have a hexagonal cross section and are highly collectible.
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:Chamber of Mines of Eastern BC (NCM)
Virtual Museum ID:19-NCM15
Date Added to VM:2019-06-11
Sample Origin:Eagle Creek, BC
Specific Site:Poorman/Kenville Mine
Datum:11 (NAD 83)
Primary Features:Au in quartz from granite
Primary Mineral Formula:Au · SiO2 · X3Y2(SiO4)3
Primary Category:native element oxide
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:Eagle Creek Plutonic suite
Geological Period:Lower Jurassic
Stratigraphic Age:174.1 to 201.3 Million Years
Geological Terrane:Quesnel, Pelly Gneiss
The Kenville (formerly known as Granite-Poorman) mine is located on the east side of Eagle Creek and the north slope of Toad Mountain, 8 kilometres west of Nelson.
The area is underlain by the Eagle Creek Plutonic suite, consisting mainly of gabbro and diorite with quartz monzonite to hornblende syenite phases present. All phases are medium- to coarse-grained and locally gneissic with varying degrees of alteration. The dominant regional structural features are broad, north-trending and east-verging folds. Quartz veins occupy gravity fault planes and cut the diorite hostrock along a northwest trend and dip 45 degrees to the northeast. Flat quartz veins occupy tension fractures created by movement along northwest-trending faults. The veins are cut by faults, some of which are occupied by lamprophyre dykes. Because they occupy regional fault planes, the quartz veins have exceptional continuity along strike and downdip.
The Kenville mine has been classified as a gold-quartz vein deposit. The mine workings include five north-northwest–trending veins hosted in variably sheared mafic intrusives. These five veins are part of the Granite-Poorman veins, which consist of six main veins and several secondary or less continuous veins. The veins strike 330 to 350 degrees, dip approximately 45 degrees northwest and have an average thickness of 0.6 metre, although they are more commonly 0.02 to 0.1 metre wide. From west to east, over a horizontal distance of 518 metres, they are the Hardscrabble, Poorman, Greenhorn, Granite (or White) and Beelzebub veins. Lesser veins occur to the east and west. The veins consist of milky to glassy quartz with pyrite and chalcopyrite occurring as the dominant sulphides. Minor galena, sphalerite, scheelite and visible gold occur within the veins. Reports from earlier development mention “rich pockets” of visible gold. Where the veins are oxidized, limonite is common with some "free gold". Scheelite is widely distributed as individual grains but rarely as significant concentrations in any given zone. Sulphides are commonly disseminated in hanging wall or footwall rocks. Ore shoots, which rake to the south, are formed at the intersection of the main veins with flatter lying offshoots; high gold values in these shoots appear coincident with galena. Hostrocks exhibit replacement of plagioclase by soda-potassic feldspar and alteration of ferromagnesian minerals to biotite and epidote.
At the Hardscrabble vein, steeply dipping faults drop the eastern block down as much as 15 metres. The largest fault has produced offset of approximately 100 metres to the left in the Granite and Greenhorn veins. Local structure is dominated by the northeast to northwest-trending, south-plunging Hall Creek syncline. To the north of the project area, a series of northwest-striking shears form a 1-kilometre-wide zone known as the Silver King shear.
Numerous adits and underground workings, most dating from the turn of the 19th century, are present on the property. The main mine workings consist of seven levels. The mine is developed from two main levels, the 2570 or lower (257 Level), and the 2750 or upper (275 Level) adits. Underground workings are extensive. The five main veins have been stoped for a combined length of over 915 metres.
The Kenville Mine was the first underground lode gold mine in British Columbia and was the largest producer in the Nelson Mining Camp Project claims. The first claims on the Granite-Poorman property were staked by I. Neil in 1888. In 1889, Eagle Creek Mining Company began milling ore from five northwest-trending veins on the northeast corner of the modern Kenville mine property. Tungsten, copper and cadmium are also present but have never been recovered in significant amounts. From 1900 to 1929, the property changed ownership seven times; from 1904 to 1929, the mine was worked almost exclusively by lessees. The property was owned and operated by these companies, in the following order: Eagle Creek Gold Mining Co., Granite Gold Mines Ltd., Duncan United Mines Ltd., Kootenay Gold Mines Ltd., Kootenay Gold Exploration Co. Ltd., Inland Mining Co., Granite-Poorman Mines Ltd. and Granite-Poorman Gold Mines Ltd. In 1932, the property was acquired by Livingstone Mining Company. The mine continued to operate intermittently until 1944.
In 1945, Kenville Gold Mines Ltd. (owned by Noranda Mines Ltd.), acquired the property and proceeded with an exploration and development program that included building a 125-tonne per day cyanide mill. Over 6096 metres of diamond drilling were completed on the Granite-Poorman property, partially from the surface in a search for hidden veins and the remainder underground to search for extensions of known veins. The mine ceased operations in 1949, though small amounts of high-grade ore were shipped to the Trail smelter in 1960 and 1961. The mill remained in operation until 1962, processing feed from local small-scale mining operations. Upon decommissioning in 1962, the mill was shut down and all usable equipment was removed from the site.
In 1969, the property was acquired by Algoma Industries and Resources Ltd. Algoma attempted to restart mine production, re-opening the 257 Level and dewatering the mine. Further efforts maintained the mine open, rebuilt the mill and attempted production. These efforts failed and in 1987 the property was sold to Coral Industries Ltd. In 1989, Coral Industries exercised their right to operate the mine, took over the care and maintenance program and began an assessment of milling operations. Production was dedicated to testing milling operations. Testing indicated the mill was not properly designed for the ore and that flotation might be a preferred recovery method. That same year, the Kenville property was amalgamated with the Venango property (082FSW087) to the west. In 1980, DeKalb Mining Corporation completed 2932 metres of diamond drilling on the Venango-Shenango and Greenwood claims. One drillhole near the Venango mine returned 11 metres of 1.01 per cent copper and 15.2 grams per tonne silver with minor gold and molybdenum (Assessment Report 24303). In 1991, Coral Industries shipped a small tonnage of ore to the Trail smelter for processing and undertook a test pit sampling program to assess metallic and trace element grades in the former Kenville mine tailings pond. Test pit results returned no values of economic significance.
In 1992, the property (including the Venango adit) was acquired by Anglo Swiss Resources Ltd. In 1994, Teck Exploration Ltd. optioned the Kenville mine property and amalgamated it with the adjacent Ron property. The Teck exploration program focused on locating a bulk minable copper-gold porphyry target. From 1994 to 1997, work included 16 diamond drillholes totalling 3083 metres, induced polarization, resistivity and ground magnetic and geochemical surveys. Low-grade porphyry-style mineralization and alteration was encountered over short intervals. Teck dropped the option in 1997. During this time, the existing mill facilities were used by Anglo Swiss to process bulk samples extracted from the Blu Starr gemstone property to the north.
Anglo Swiss resumed exploration in 2005. Work focused on an area on the west side of Eagle Creek and consisted of GPS mapping, geochemical soil sampling and excavator trenching. The program continued into 2006 with trenching reclamation, soil sampling and the reconstruction of a 40-metre length of the 257 adit. In 2007 and 2008, Anglo Swiss completed 15 500 metres of drilling over 50 holes near the Kenville mine. The purpose of the program was to further define the Granite-Poorman vein system and to continue exploration for porphyry-style mineralization. Results of this program are unknown.
In 2009, work completed by Anglo Swiss Resources consisted of 680 line kilometres of airborne time-domain electromagnetic geophysical surveys, surface diamond drilling, underground rehabilitation and underground drilling. Ten diamond drillholes were completed at four sites on the east side of Eagle Creek, totalling 3568.4 metres of NQ2-size core. The aim of the drilling was to intersect the inferred extension of the Hardscrabble and Yule veins. Analysis of the core revealed quartz veins ranging from 1 to 40 centimetres thick, typically containing up to 30 per cent fine-grained pyrite with local chalcopyrite and chlorite. The veins commonly imparted a silica-pyrite halo up to 15 centimetres into the hostrock. In 2010, Anglo Swiss Resources completed a diamond drilling program intending to test the southern extension of high-grade veins from the Kenville mine. Five holes were completed and a sixth was abandoned at 90 metres depth. In total, 2982 metres were drilled. From 2010 to 2012, 18 diamond drillholes were completed from eight locations on the Kenville property and one location on the adjacent Ron property. In total, 9375.53 metres of core were drilled, including 8863.17 metres of NQ2-size core and 512.36 metres of BTW core. The drilling successfully identified the southern extensions of the vein systems targeted in the Kenville and Venango mine workings. In 2013, Anglo Swiss sold the Kenville gold property to Eagle Creek Gold Corporation.
The Granite-Poorman veins produced mainly gold with silver but the mill has been used at various periods to process ores from other properties that might have been richer in base metals. In recent years, some of the granitic rock has been used as a construction material (Granite MINFILE 082FSW342). A 1985 report by P.J. Stantos stated that indicated and inferred resources above the 257 (main mine adit) level were 294 800 tonnes grading 16.73 grams per tonne gold (www.anglo-swiss.com).
At end of life, mine production totalled 180 740.23 tonnes (199 232 short tons) averaging 9.07 grams (0.32 ounce) per tonne gold and 3.96 grams (0.14 ounce) per tonne silver (Assessment Report 24303). In total, the mine produced 1849.41 kilograms (65 236 ounces) of gold, 784.88 kilograms (27 686 ounces) of silver, 23.48 tonnes (51 782 pounds) of lead and 15.15 tonnes (33 393 pounds) of zinc (Assessment Report 32837).
A 1995 Teck Exploration drilling program returned 8.7 metres of 1.03 per cent copper and hosted within a newly discovered westward-dipping quartz vein 0.25 metre of coarse, massive pyrite grading 82.15 grams per tonne gold and 31 grams per tonne silver.
Significant results from the 2009 Anglo Swiss diamond drill program are shown in the table below (Assessment Report 31623).
Interval Gold Silver Copper
(metres) (parts per million) (parts per million) (parts per million)
0.55 10.55 5.71 699
0.22 33.7 24.8 115
0.5 4.48 12.5 1100
1.14 14.49 20.24 3332
3.2 17.29 34.34 8405
Significant assay results returned from the 2010 drill program include
• 0.5 metre of 111.5 grams per tonne gold and 58.1 grams per tonne silver,
• 0.88 metre of 88.1 grams per tonne gold and 130 grams per tonne silver,
• 0.46 metre of 59.8 grams per tonne gold and 31.8 grams per tonne silver, and
• 0.28 metre of 47.2 grams per tonne gold and 51.4 grams per tonne silver (Assessment Report 32837).
Results from the 2010 to 2012 drilling included 85 samples that returned assays with greater than 5 grams per tonne gold, including 21 quartz vein intersections returning greater than 1 ounce per tonne (34.29 parts per million) gold (Assessment Report 32839).