Vancouver — The discovery of coarse placer gold at the mouth of the Nicoamen River in 1857 sparked a gold rush that a year later drew an estimated 20,000 prospectors and fortune-seekers to the Fraser and Thompson Rivers of southern British Columbia. While not a full-blown gold rush yet, a series of significant gold discoveries have triggered renewed interest in the historic region, now shaping up to be the province’s newest epithermal gold district.
The initial discoveries in the Spences Bridge gold belt were made by
Easy access was one attraction, as the area was a mere 3-hour drive from Vancouver, B.C. Another was the unique geology of the showing, which was partially exposed by logging roads cut decades earlier.
“It looked like it had epithermal characteristics, yet the surrounding region wasn’t known for its epithermal potential, so we decided to see what we could find in the literature,” Balon recalls.
Government files revealed scant information, except for reports of elevated gold-in-stream sediment samples collected by government geologists in 1981, but not analyzed until 1994. That data was published in an open-file report that showed a number of strong gold-in-silt anomalies, yet the results were never followed up, and no claims were staked to cover the anomalies.
“The area was wide open then,” Balon says. “There were very few Min-File (gold) occurrences, and most were in other rock types, but the (stream-sediment) samples were enough to pique my interest.”
Balon also scoured historical books and reports documenting placer mining in the general Lytton-Merritt region, and hit literal pay dirt. Many of the old placer workings were downstream of the areas that had returned elevated gold from stream-sediment samples.
Balon’s initial round of prospecting began in the summer of 2001, and focused on two of the highest-order government stream-sediment anomalies. Follow-up stream-sediment sampling in the drainage confirmed the government values, while subsequent prospecting in the general area yielded encouraging results.
“We got good numbers, always above background, which was low for this particular region,” Balon says. “We found gold in the drainages, and it was angular stuff too, so we knew we were onto something.”
Balon and colleague Voytek Jakubowski resumed prospecting upstream of the government anomalies, and in the local area, in the fall of 2001. They discovered numerous gold-bearing quartz vein and breccia float occurrences with classic epithermal textures. Sampling of these occurrences yielded values of up to 43.3 grams gold, as well as associated anomalous geochemical signatures (arsenic, antimony, mercury) characteristic of epithermal systems.
These results and the presence of widespread alteration in a nearby rock unit prompted staking of what is now part of the Prospect Valley project. The project has since been optioned to
After staking the initial 40-unit block (now part of Prospect Valley) in 2001, Almaden carried out a broader prospecting program in 2002, an effort complicated at times by overburden that obscured prospective areas beyond the reach of an excavator. Balon recalls that in some cases when he hit bedrock, samples returned anomalous pathfinder elements, but no gold values.
Balon returned in the spring of 2003 and decided to carry out regional silt and sediment sampling higher in the drainages. “We ended up with a good cluster of anomalies, and then found a bit of float along a logging road, along with scattered chips of quartz in soils.”
As the sampling progressed, a north-northeast trend emerged, and more claims were staked to cover the apparent trend of mineralization. Later that year, with some digging, a siliceous zone was found and sampled, with initial grab samples returning 6.5 grams gold.
Gold rush origins
More digging revealed an in situ vein/breccia showing over a 0.5- to 1.5-metre strike length. Chip sampling returned high grades of gold. It was then obvious that the region was prospective for lode gold deposits that (over time) had likely shed the gold triggering the Fraser/Thompson gold rush.
“We knew then we were in the right football field,” Balon says.
During the winter of 2003-2004, Balon and his team again examined government and other mineral data to get a handle on the structural regime governing the district. This effort “turned up some interesting stuff,” according to Balon, in particular, similarities to the Republic Graben in Washington and southern British Columbia. (The Republic district hosts a number of known gold deposits).
Work to date suggests that the dominant structural feature — the Spius Creek Fault — is the major conduit for mineralization. This fault is connected with the Lornex Fault, which in turn hosts large copper deposits, such as the famous Highland Valley mine near Logan Lake.
Balon says the structural understanding triggered yet another staking effort to consolidate prospective ground. Many of the claims were the first ever recorded in various areas of interest, notwithstanding the short distance from Vancouver. The expanded land package does include some ground previously held by other companies, primarily for their copper potential.
By this point, Almaden had discovered additional areas of clay-carbonate alteration and quartz-veining representative of low-sulphidation epithermal gold-silver systems. The presence of high-grade gold and associated pathfinder elements over widespread areas began attracting attention from other companies.
Even so, the region received minimal market attention until mid-2005, in part because most companies were focused on advanced projects with defined resources. The region attracted serious attention when a first-pass drill program returned extraordinary results from ground staked by Almaden, and optioned to
The Skoonka Creek project was acquired entirely by staking from 2003 to early 2005. Initial field work by Almaden revealed quartz-vein rubble along a road-cut that was sampled and assayed 1.3 grams gold. Follow-up work in 2003 revealed other mineralized quartz float occurrences, which led to the discovery of an in situ quartz/breccia vein. Hand-trenching and sampling of the Discovery Vein returned encouraging values.
In the fall of 2004, the high-grade JJ showing was found 3 km southwest of the 2003 Discovery zone, on an apparent sub-parallel east-northeast structural trend. Two closely spaced veins were stripped and sampled, and returned values ranging from 14.93 grams gold to 55.75 grams gold from vein material, and 1.25-8.85 grams gold from altered wall-rock.
The initial encouraging results were confirmed by Strongbow’s subsequent drill program of about 1,200 metres. Seven of the holes tested the JJ vein system over a 350-metre strike length, with all seven holes intersecting mineralization. In addition to the hole mentioned above, other highlights include 4.1 metres of 6.41 grams gold per tonne, and 3.31 metres of 23.5 grams.
Skoonka Creek is the most advanced and one of the largest of seven properties assembled by Almaden in the emerging Spences Bridge gold belt. Strongbow can earn a 60% interest by spending $4 million on exploration and issuing shares over six years.
Strongbow recently picked up seven new properties covering about 384 sq. km in the district. The company notes that initial
geochemical surveys over several of the properties returned results “confirming the presence of gold stream-sediment anomalies equal to or stronger than the gold stream-sediment anomalies that originally drew attention to the Skoonka Creek area.”
Exploration
Strongbow plans an aggressive work program for this spring, including stream and soil geochemical surveys, prospecting and bedrock mapping, followed by more advanced programs as warranted.
Consolidated Spire is also continuing to explore its ground in the region. The company’s mapping, trenching and sampling program in 2005 defined a strong gold and multi-element soil geochemical anomaly measuring more than 3,000 metres long by 200-400 metres wide. Gold-silver-bearing quartz veins were also identified by hand-trenching within separate areas along trend of the anomaly.
Subsequent work later in the 2005 season included additional soil sampling to provide better coverage between two prospect areas, and additional hand-trenching. The RM gold and multi-element soil anomaly now measures 3,500 metres long by 200-400 metres wide.
The hand trenches exposed sheeted and stockwork quartz veining in bedrock, with all 11 trenches returning anomalous values. Results include 0.85 gram gold per tonne across 4.9 metres, 1.38 grams across 5.7 metres, with individual samples returning up to 5.48 grams across 1 metre.
Based on trace-element geochemistry and mineral textures, the company notes that this trenching probably tested the upper portions of the epithermal gold system, and sees potential for higher grades at depth.
A ground geophysical program is planned for early 2006 to better define targets for a spring drill program.
On its own, Almaden is planning to explore several projects that it owns outright in the region. Including the joint-ventured Prospect Valley and Skoonka Creek projects, the company owns or holds interests in seven properties totalling 425 sq. km.
Three recently acquired properties — Ponderosa, Gillis Lake and Brookmere — have no previously documented mineral occurrences. Two wholly owned projects, Merit and Nicoamen River, have been tested by early stage prospecting and sampling programs.
Almaden’s Merit project adjoins Spire’s Prospect Valley project. The company’s summer 2005 program included geochemical and rock sampling, geological mapping and hand-trenching on two of three mineralized zones identified to date. Results are not all in hand, but 115 reconnaissance rock samples returned average values of 0.97 gram gold, with values up to 7.9 grams. Three contiguous channel samples averaged 7.2 grams across a 1.8-metre true-width section of quartz veining and altered host-rock exposed by trenching in the main (Sullivan Ridge) zone.
Results from grid soil sampling, road-cut soil sampling, prospecting and reconnaissance rock sampling were carried out at the Nicoamen River project in 2005, along with limited hand-trenching and geological mapping. Results are still pending, but 12 grab samples of quartz vein float collected in 2004 returned gold assays ranging from 0.25 gram to 55.5 grams gold. The source of the float has not yet been found.
Almaden is encouraged by results generated from the emerging district to date, and expects further discoveries will be made in the years ahead. A number of companies and prospectors have picked up ground in the district, with most companies looking to start initial exploration programs this spring.
The list includes
While it’s still early days, the Spences Bridge gold belt has generated increased interest in B.C.’s gold potential. Balon’s role in the discovery earned him the H.H. “Spud” Huestis Award for excellence in prospecting and mineral exploration by the B.C. and Yukon Chamber of Mines. The award will be presented to Balon at the Mineral Exploration Roundup to be held in Vancouver in late January.
Balon says several associates made important contributions to the series of discoveries in the emerging belt, including geologists Jan Tindle, Barrie Sullivan, and David Ritcey. He adds that the Spences Bridge epithermal gold belt owes much to “boot-and-hammer” prospecting and good field work, as the forest cover and incised canyons of the region make exploration more challenging than in terrains where geological features can be easily detected using satellite data. Despite these challenges, results to date have shown that British Columbia has potential for important new gold discoveries.
“The big moral of the story here is that you don’t have to go to the ends of the earth to find something,” Balon says. “There’s still potential to make discoveries close to home.”
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