Friday 21st October 2016

Resource Clips

Posts tagged ‘gold’

Copper North Mining drills porphyry copper-gold in northern B.C.

October 20th, 2016

by Greg Klein | October 20, 2016

Having released a PEA for its Carmacks copper-gold-silver project in the Yukon the previous week, Copper North Mining TSXV:COL reported drill results from the northern British Columbia Thor project on October 20. After two previous holes on the 20,000-hectare property’s Thor West area came up dry, a Thor East hole did better:

Hole TH16-01

  • 0.14% copper and 0.045 g/t gold over 107.6 metres, starting at 11.65 metres in downhole depth
  • (including 0.23% copper and 0.069 g/t gold over 37.13 metres)
  • (which includes 0.28% copper and 0.087 g/t gold over 23.85 metres)

True widths were unavailable.

Copper North Mining drills porphyry copper-gold in northern BC

Samples from the property’s Thor East area
show oxide-weathered granodiorite.

Traces of copper continue beyond that intercept to the end of the hole at 169.16 metres, the company stated. “The transition from stronger mineralization and quartz-veining at the top of the hole to weaker copper mineralization and phyllic alteration at depth suggests that drill hole TH16-01 may flank a mineralized porphyry centre.”

Next steps would include ground surveys at Thor East and evaluating multiple geochemical targets and alteration zones, the company added. Field work has already identified multiple targets over a four-by-six-kilometre area southeast of TH16-01.

“The large area of porphyry alteration and gossan zones remain an attractive exploration target,” commented president/CEO Harlan Meade. “The Thor project provides Copper North with an opportunity to explore for porphyry copper-gold type mineralization in the slopes and valleys 20 kilometres to the south of the Kemess South mine and mill complex.”

The former mine now lies within AuRico Metals’ (TSX:AMI) Kemess Underground gold-copper-silver property.

Copper North holds a 100% option on Thor, which has a road and power line passing through the property.

The company closed private placements totalling $279,050 this month.

Read more about Copper North Mining.

Nickel One Resources moves closer to PGE-copper-nickel acquisition in Finland

October 19th, 2016

by Greg Klein | October 19, 2016

Nickel One Resources moves closer to Finnish PGE-copper-nickel acquisition

Over $10 million in previous work has given Lantinen Koillismaa
resource estimates for two potential open pits.

Nickel One Resources’ (TSXV:NNN) Finland entry took another step forward with a binding letter agreement announced October 19. Already holding the Tyko project in western Ontario, Nickel One would get a 100% interest in Finore Mining’s (CSE:FIN) Lantinen Koillismaa platinum group element-copper-nickel project in north-central Finland. An LOI was announced in August.

The property would come through the purchase of Finore subsidiary Nortec Minerals Oy in a deal costing five million shares and 2.5 million warrants exercisable at $0.12 for two years. Nickel One has paid $50,000, which would be applied to a private placement of up to $100,000 into Finore following due diligence.

Benefiting from over $10 million in previous work, LK has 2013 resource estimates for two potential open pits.

The Kaukua deposit shows:

  • indicated: 10.4 million tonnes averaging 0.73 g/t palladium, 0.26 g/t platinum, 0.08 g/t gold, 0.15% copper, 0.1% nickel and 65 g/t cobalt

  • inferred: 13.2 million tonnes averaging 0.63 g/t palladium, 0.22 g/t platinum, 0.06 g/t gold, 0.15% copper, 0.1% nickel and 55 g/t cobalt

The Haukiaho deposit has three zones totalling:

  • inferred: 23.2 million tonnes averaging 0.31 g/t palladium, 0.12 g/t platinum, 0.1 g/t gold, 0.21% copper, 0.14% nickel and 61 g/t cobalt

The acquisition would bring Nickel One into “a mining-friendly jurisdiction with some of the best infrastructure in the world,” commented president Vance Loeber. The project also provides “a foothold in Finland from which we will be taking a hard look at other opportunities to continue to build a strong portfolio of projects,” he added.

Read more about Nickel One Resources and the Lantinen Koillismaa acquisition.

Pistol Bay Mining to take largest position in Ontario’s VMS-rich Confederation Lake

October 19th, 2016

by Greg Klein | October 19, 2016

Pistol Bay Mining to take largest position in Ontario’s VMS-rich Confederation Lake

Pistol Bay’s holdings will cover a 31-kilometre length of the VMS-rich Confederation Lake greenstone belt.


A new acquisition would make Pistol Bay Mining TSXV:PST the biggest claimholder in Ontario’s Confederation Lake greenstone belt. The 5,136-hectare package comprises all the regional claims held by AurCrest Gold TSXV:AGO and includes a zinc-copper-silver resource as well as an historic, non-43-101 estimate. Along with Pistol Bay’s optioned Dixie and Dixie 3 properties, the letter of intent announced October 19 would increase the company’s holdings to 7,050 hectares on the volcanogenic massive sulphide-rich belt.

With three cutoff grades, the package’s Arrow zone has resources showing:

3% zinc-equivalent cutoff

  • indicated: 2.07 million tonnes averaging 5.92% zinc, 0.75% copper, 21.1 g/t silver and 0.58 g/t gold

  • inferred: 120,550 tonnes averaging 2.6% zinc, 0.56% copper, 18.6 g/t silver and 0.4 g/t gold

5% zinc-equivalent cutoff

  • indicated: 1.76 million tonnes averaging 6.75% zinc, 0.79% copper, 22.3 g/t silver and 0.61 g/t gold

  • inferred: 51,630 tonnes averaging 3.86% zinc, 0.79% copper, 23.9 g/t silver and 0.58 g/t gold

10% zinc-equivalent cutoff

  • indicated: 633,000 tonnes averaging 14.3% zinc, 1.11% copper, 31.7 g/t silver and 0.85 g/t gold
Pistol Bay Mining to take largest position in Ontario’s VMS-rich Confederation Lake

Pistol Bay’s Dixie properties have been
undergoing field work and a review of historic data.

Additionally, the Copperlode A or Fredart zone has an historic, non-43-101 estimate of 425,000 tonnes averaging 1.56% copper. Exploration in the 1970s produced samples up to 1.46% molybdenum.

The 100% option would cost $25,000 and one million shares on closing and $25,000 90 days later, as well as $50,000 and one million shares on each of the four anniversaries following closing. In addition to regulatory approvals, the transaction needs the consent of Glencore plc, whose rights to the Confederation Lake property include a 2% NSR.

The companies expect to close within a week.

“Pistol Bay proposes an ambitious exploration program that will not only pursue existing targets and known VMS deposits, but will use the latest airborne geophysical survey technologies to explore the whole area to a greater depth than was possible in the past,” said president Charles Desjardins.

Earlier this month the company announced MPH Consulting will review historic geophysical data on Pistol Bay’s Confederation Lake-region Dixie properties, where field work began in September. Historic drilling has found zinc, copper and silver, while the recently optioned Dixie 3 project comes with an historic, non-43-101 estimate of 82,500 tonnes averaging 1% copper and 10% zinc.

The company has a joint venture with a Rio Tinto NYSE:RIO subsidiary on the C-5 uranium property in Saskatchewan’s Athabasca Basin. Having already earned 75% of its option, Rio has stated its intention to acquire the full 100%.

Pistol Bay closed a $563,450 private placement last August.

Golden Dawn Minerals to expand southern B.C. portfolio of past-producers

October 18th, 2016

by Greg Klein | October 18, 2016

Golden Dawn Minerals to expand southern B.C. portfolio of past-producers

Several former mines dot southern B.C.’s Greenwood camp.


Another 10,400 hectares with former mines would increase Golden Dawn Minerals’ (TSXV:GOM) presence in southern British Columbia’s historic Greenwood mining camp. Under a binding letter of intent announced October 18, the company would acquire Kettle River Resources, a subsidiary of New Nadina Explorations TSXV:NNA. Golden Dawn already has a portfolio of former mines within a 15-kilometre radius of its 200-tpd Greenwood mill, about 500 kilometres east of Vancouver.

The new acquisition would include the Tam O’Shanter project, the Sylvester K zone, some tailings sites, the former Phoenix mine and the Bluebell/Oro Denoro Eholt properties.

Golden Dawn has previously explored Tam O’Shanter along with a contiguous property, identifying an inferred resource for both.

Phoenix was mined between 1900 and 1978, producing over a million ounces of gold, 18 million ounces of silver and 575 million pounds of copper. Golden Dawn sees potential for new copper-gold finds.

Golden Dawn Minerals to expand southern B.C. portfolio of past-producers

Golden Dawn’s current portfolio includes the Greenwood mill.

The Sylvester K zone has a strike length of about 150 metres, with thickness up to 12 metres. Mining in 1989 extracted a reported 5,090 tonnes of material averaging 5.1 g/t gold.

Three tailings sites are associated with Phoenix. Metallurgical studies suggest re-grinding and cleaner flotation might offer potential for a copper-gold concentrate.

The Bluebell/Oro Denoro Eholt property has undergone exploration and mining since the 1890s, with a number of recent showings. Among the results, trenching at the Minnie Moore area in 2007 found silver grading 414 g/t over 8.5 metres, 1,044 g/t over 6.2 metres and 432 g/t over 5.8 metres. A drill core assay showed 77.3 g/t silver over 5.3 metres.

The properties come with a database representing 120 years of mining and exploration records.

Subject to a 90-day due diligence period and approvals, the package would cost Golden Dawn a non-refundable $80,000 on signing and another $15,000 by November 26. Those deposits would form part of a $1-million payment due on closing. New Nadina would also get $600,000 in Golden Dawn shares and a 1% NSR, half of which may be bought back. The companies expect to consummate by about January 31.

Late last month Golden Dawn issued a progress report on its work to reactivate the former May Mac, Lexington and Golden Crown mines, along with the nearby Greenwood mill. Trial mining could begin at Lexington in Q2 or Q3 next year, the company reported. Golden Crown, another gold-copper past-producer, could re-open in Q2 2018.

Golden Dawn has also been drilling May Mac and the Amigo past-producer about a kilometre south. The company expects to close a metals streaming deal this month.

Adding Yukon gold and silver

October 17th, 2016

Copper North Mining brings copper mining costs south


Look at development-ready copper projects and “you’ll find most of them are very large, multi-billion-dollar projects,” says Copper North Mining TSXV:COL president/CEO Harlan Meade. “And if you look at the smaller projects, there aren’t that many that would be in the lower decile of the cost curve.” A revised PEA announced October 12 brought the company’s Carmacks project into that category by incorporating gold and silver into a new metallurgical flowsheet. But Meade sees further potential for the south-central Yukon property with additional improvements, a new resource—completed but not yet entered into the mine plan—and an optimistic price scenario for the conductive commodity.

Metallurgy was key to the new PEA. A 2012 feasibility study “was based on a copper-only heap leach operation and that suited the higher metal prices of the day,” Meade explains. In 2014 Copper North factored gold and silver into a revised PEA. The current PEA now calls for agitated tank leaching of copper oxides to produce cathode copper. That would be followed by agitated tank leach cyanidation and carbon-in-leach processing to produce gold and silver doré bars. Considering gold and silver credits, the open pit would produce copper at US$1.08 a pound.

Copper North Mining brings copper mining costs south

Carmacks’ new resource has yet to be worked into the mine plan.
Further improvements could come from resource expansion,
improved silver recovery and eventual sulphide recovery.

The PEA sees Carmacks averaging 30 million pounds of cathode copper, 19,500 ounces of gold and 21,600 ounces of silver annually over a seven-year mine life.

Pre-production capex comes to $214.7 million, with total capex of $263.6 million and after-tax payback in 5.3 years. Using an 8% discount rate, the pre-tax NPV comes to $11.9 million with a 9.4% IRR. After taxes, the numbers show minus-$11.4 million and 6.6%.

That’s based on copper at $2.50 a pound, with gold at $1,300 and silver at $17.50 an ounce. At $2.75 copper, the pre-tax numbers show a $55.9-million NPV and 14.2% IRR. Should copper hit $3, pre-tax numbers climb to $99.8 million and 18.7%.

“Some people are using $2.75,” says Meade. “I wouldn’t blame them because if you look at the fundamentals of copper I think we’re going to see it in the $2.50 to $2.75 range towards the end of next year, and that would be the environment we’d be financing in.”

Directly sourced equipment helps cut capex. “A lot of equipment used today is made in China and brought in by U.S. suppliers. If we go straight to the source we get a very, very significant reduction.”

A pre-feas priority will be last January’s maiden resource for three zones not included in the current PEA. Located south of the proposed open pit that incorporates zones 1, 4 and 7, new zones 12, 13 and 2000S show the following totals:

Oxide and transitional mineralization

  • measured and indicated: 3.7 million tonnes averaging 0.5% total copper, 0.35% acid-soluble copper, 0.132 g/t gold, 2.011 g/t silver and 0.15% copper sulphide

  • inferred: 822,614 tonnes averaging 0.42% total copper, 0.28% acid-soluble copper, 0.119 g/t gold, 1.91 g/t silver and 0.14% copper sulphide

Sulphide mineralization

  • measured and indicated: 3.73 million tonnes averaging 0.6% total copper, 0.06% acid-soluble copper, 0.128 g/t gold, 2.288 g/t silver and 0.55% copper sulphide

  • inferred: 4.37 million tonnes averaging 0.55% total copper, 0.04% acid-soluble copper, 0.123 g/t gold, 2.081 g/t silver and 0.52% copper sulphide

Each of the three zones remains open along strike and at depth. Oxides begin at surface and extend to shallow depths. Sulphides occur at depths as shallow as 50 metres, the report stated.

Totals for all six zones come to:

Oxide and transitional mineralization

  • measured and indicated: 15.7 million tonnes averaging 0.94% copper, 0.74% acid-soluble copper, 0.379 g/t gold and 3.971 g/t silver

  • inferred: 900,000 tonnes averaging 0.45% copper, 0.3% acid-soluble copper, 0.119 g/t gold and 1.9 g/t silver

Sulphide mineralization

  • measured and indicated: 8.1 million tonnes averaging 0.68% copper, 0.178 g/t gold and 2.332 g/t silver

  • inferred: 8.4 million tonnes averaging 0.63% copper, 0.15 g/t gold and 1.994 g/t silver

Meade wants additional drilling in and around the three new zones this spring to upgrade the inferred numbers and maybe expand the resource too. “Then we’ll do some engineering to design a pit to add to the existing plan,” he says.

And we’ve still got a lot of room for exploration and expansion. I think there’s significantly more copper oxides and sulphides if one turns on the drills.—Harlan Meade,
president/CEO of
Copper North Mining

Another priority will be silver recovery, now down to 9.4%, compared with 85.5% for copper and 84.4% for gold. Silver took a hit when tests sped up the leach process by increasing heat. “But we’ll probably get it back,” says Meade.

At some point the sulphides should undergo metallurgical studies to produce either cathode copper or a concentrate. “There’s work to be done that might significantly extend the mine life,” he points out. “And we’ve still got a lot of room for exploration and expansion. I think there’s significantly more copper oxides and sulphides if one turns on the drills.”

Permitting could begin in fall 2017. “Carmacks has already been through the process and I think this proposal would be a lot simpler than the previous heap leach project,” he maintains. “I think the regulators will find much of this has been reviewed before so we think it’ll take about eight months. If that’s done you could begin production in early 2019.”

Community relations look positive, he adds. “My predecessor spent a lot of time building a relationship with two first nations. They’re keen to get started on a benefits agreement. They’re supportive of what we’re doing and hope we get this going sooner than later.”

The 4,933-hecatre project has nearby water, sits 11 kilometres from power and has 13 kilometres of road and trail access to a seasonal road that’s 34 kilometres from the town of Carmacks.

Having kept costs down to the lower decile, “we think Carmacks has a very good probability of being financed fairly quickly, especially if we see a small improvement in the copper price. We see it developing quickly and probably becoming Canada’s next copper mine. It’s financeable and it’s a low-cost producer, what more could you ask for? I guess a little more mine life, but we’re working on that.”

The company has also been active in northwestern British Columbia, where summer drilling has wrapped up on the Thor copper-gold porphyry project. Meade expects to release assays shortly.

This month Copper North closed private placements totalling $279,050.

Dunnedin Ventures finds gold synergies at its Nunavut diamond deposit

October 17th, 2016

by Greg Klein | October 17, 2016

Diamonds remain the focus of Dunnedin Ventures’ (TSXV:DVI) Kahuna project but evidence of gold offers additional potential, the company announced October 17. Recent till sampling on the Nunavut property brought positive gold results, as did historic rock samples.

Of 129 till samples taken last year, 84 showed anomalous results of 50 ppb gold or better. Twelve samples assayed greater than 1,000 ppb, with one sample reaching 5,930 ppb.

Dunnedin Ventures finds gold synergies at its Nunavut diamond deposit

Evaluation of gold grains suggests local bedrock sources, Dunnedin emphasized.

“One area of strong gold-in-till concentration occurs at the 10-square-kilometre hinge domain of a previously untested folded metasediment belt where a number of diamond-bearing kimberlites including PST, Notch and 07KD-24 are also located, suggesting proximal bedrock sources of gold and diamonds,” the company added.

Previous analysis of the till samples revealed diamond indicator minerals suggesting potential extensions to Kahuna’s known kimberlites, as well as additional kimberlite targets prospective for diamonds.

Historic work included 97 rock samples that assayed between 0.05 and 2.52 g/t gold.

The 60,000-hectare property sits about 25 kilometres from the Hudson Bay hamlet of Rankin Inlet and about 10 kilometres from Agnico Eagle Mines’ (TSX:AEM) Meliadine gold project, which could potentially begin production in 2020. An all-season trail under construction from Rankin Inlet to another Hudson Bay hamlet, Chesterfield Inlet, would pass within a few kilometres of Kahuna. Dunnedin has pledged $25,000 to the project. Longer-term plans would include a link to the current all-season road to Meliadine.

Kahuna has a January 2015 inferred resource for near-surface diamond deposits on the Notch and Kahuna kimberlites, 12 kilometres apart:

  • Kahuna (+0.85 mm cutoff): 3.06 million tonnes averaging 1.04 carats per tonne for 3.19 million carats
  • (+1.18 mm cutoff): 0.8 ct/t for 2.45 million carats

  • Notch (+0.85 mm cutoff): 921,000 tonnes averaging 0.9 ct/t for 829,000 carats
  • (+1.18 mm cutoff): 0.83 ct/t for 765,000 carats

  • Total (+0.85 mm cutoff): 3.99 million tonnes averaging 1.01 ct/t for 4.02 million carats
  • (+1.18 mm cutoff): 0.81 ct/t for 3.22 million carats

Both dykes remain open along strike and at depth.

Sample recovery from the project’s PST kimberlite showed 96 commercial-sized diamonds totalling 5.34 carats.

Read more about Dunnedin Ventures.

See Chris Berry’s report on long-term diamond demand.

Ottawa resident Larry Mantha recounts how a dog dug up a nugget in his front yard

October 14th, 2016

…Read more

Equitas Resources releases assays, plans development of Brazil gold project

October 13th, 2016

by Greg Klein | October 13, 2016

Good gold grades over wide, near-surface intercepts instil further confidence in Equitas Resources’ (TSXV:EQT) Cajueiro project in central Brazil. Reported October 13, two infill holes on the Crente zone “lend further support for the potential of Crente to represent a significant portion” of the property’s open pit component, stated VP of exploration Everett Makela.

The drilling targetted a former garimpeiro pit to follow up on an historic hole that found 2.37 g/t gold over 31 metres, including 4.15 g/t over 9.4 metres. The new assays show:

Hole CJO 094

  • 1.12 g/t gold over 31 metres, starting at 90 metres in downhole depth
  • (including 2.2 g/t over 4 metres)
Equitas Resources releases assays, plans development of Brazil gold project

A close-up shows 8.2 g/t gold over one metre.

Hole CJO 095

  • 1.03 g/t over 29 metres, starting at 20 metres
  • (including 3.14 g/t over 4 metres)
  • (which includes 8.2 g/t over 1 metre)

True widths weren’t available.

The results follow a summer program of 37 holes totalling 1,756 metres at the Baldo zone that produced 33 near-surface mineralized intervals. Equitas plans to incorporate this year’s drilling into an updated resource estimate. The project’s current resource uses a 0.25 g/t cutoff, with four zones of sulphides totalling:

  • indicated: 8.64 million tonnes averaging 0.771 g/t for 214,100 ounces gold

  • inferred: 9.53 million tonnes averaging 0.664 g/t for 203,500 ounces

Four zones of oxides total:

  • inferred: 1.37 million tonnes averaging 1.775 g/t for 78,400 ounces

While focusing on the more metallurgically amenable oxides, Equitas plans to transform the former alluvial operation by installing a carbon-in-leach plant. Under the direction of newly appointed Brazil general manager Sergio Aquino, the company has design and costing underway for a 600-tpd plant that would process material from an upcoming bulk sampling program.

During his 35-year career Aquino headed diamond exploration for Rio Tinto do Brasil, led exploration and field operations of alluvial gold deposits, co-founded Serabi Mining PLC and served on a municipal environmental council.

Last summer a 1,324-hectare area of Cajueiro underwent a high-resolution topographic survey via an unmanned aerial vehicle. Results will help guide further surveys.

Equitas also announced termination of a private equity financing that would have included US$5 million in revolving loans and a US$1-million warrant exercise.

Cajueiro forms part of a 184,410-hectare Brazilian portfolio that came with Equitas’ acquisition of Alta Floresta Gold last spring.

Read more about Equitas Resources’ Cajueiro project.

Pushing the boundaries

October 12th, 2016

Technology opens new mining frontiers, sometimes challenging human endurance

by Greg Klein

This is the second of a two-part feature. See Part 1.

“Deep underground, deep sky and deep sea” comprise the lofty goals of Three Deep, a five-year program announced last month by China’s Ministry of Land and Resources. Part 1 of this feature looked at the country’s ambitions to take mineral exploration deeper than ever on land, at sea and into the heavens, and also outlined other countries’ space programs related to mineral exploration. Part 2 delves into undersea mining as well as some of the world’s deepest mines.

Looking to the ocean depths, undersea mining has had tangible success. De Beers has been scooping up alluvial diamonds off southwestern Africa for decades, although at shallow depths. Through NamDeb, a 50/50 JV with Namibia, a fleet of six boats mines the world’s largest-known placer diamond deposit, about 20 kilometres offshore and 150 metres deep.

Technology opens new mining frontiers, sometimes pushing human endurance

Workers at AngloGold Ashanti’s Mponeng operation
must withstand the heat of deep underground mining.

Diamond Fields International TSXV:DFI hopes to return to its offshore Namibian claims, where the company extracted alluvial stones between 2005 and 2008. The company also holds a 50.1% interest in Atlantis II, a zinc-copper-silver deposit contained in Red Sea sediments. That project’s now on hold pending a dispute with the Saudi Arabian JV partner.

With deeper, more technologically advanced ambitions, Nautilus Minerals TSX:NUS holds a mining licence for its 85%-held Solwara 1 project in Papua New Guinea waters. A seafloor massive sulphide deposit at an average depth of 1,550 metres, its grades explain the company’s motivation. The project has a 2012 resource using a 2.6% copper-equivalent cutoff, with the Solwara 1 and 1 North areas showing:

  • indicated: 1.03 million tonnes averaging 7.2% copper, 5 g/t gold, 23 g/t silver and 0.4% zinc

  • inferred: 1.54 million tonnes averaging 8.1% copper, 6.4 g/t gold, 34 g/t silver and 0.9% zinc

Using the same cutoff, the Solwara 12 zone shows:

  • inferred: 2.3 million tonnes averaging 7.3% copper, 3.6 g/t gold, 56 g/t silver and 3.6% zinc
Technology opens new mining frontiers, sometimes pushing human endurance

This Nautilus diagram illustrates
the proposed Solwara operation.

A company video shows how Nautilus had hoped to operate “the world’s first commercial high-grade seafloor copper-gold mine” beginning in 2018 using existing technology from land-based mining and offshore oil and gas. Now, should financial restructuring succeed, Nautilus says it could begin deployment and testing by the end of Q1 2019.

Last May Nautilus released a resource update for the Clarion-Clipperton Fracture Zone in the central Pacific waters of Tonga.

Another deep-sea hopeful, Ocean Minerals last month received approval from the Cook Islands to explore a 12,000-square-kilometre seabed expanse for rare earths in sediments.

A pioneer in undersea exploration, Japan’s getting ready for the next step, according to Bloomberg. A consortium including Mitsubishi Heavy Industries and Nippon Steel & Sumitomo Metal will begin pilot mining in Chinese-contested waters off Okinawa next April, the news agency stated. “Japan has confirmed the deposit has about 7.4 million tons of ore,” Bloomberg added, without specifying what kind of ore.

Scientists are analyzing data from the central Indian Ocean where nodules show signs of copper, nickel and manganese, the Times of India reported in January. The country has a remotely operated vehicle capable of an unusually deep 6,000 metres and is working on undersea mining technology.

In August the World Nuclear News stated Russia is considering a nuclear-powered submarine to explore northern seas for mineral deposits. A government report said the sub’s R&D could put the project on par with the country’s space industry, the WNN added.

If one project alone could justify China’s undersea ambitions, it might be a 470.47-ton gold deposit announced last November. Lying at 2,000 metres’ depth off northern China, the bounty was delineated by 1,000 workers and 120 kilometres of drilling from 67 sea platforms over three years, the People’s Daily reported. Laizhou Rehi Mining hopes to extract the stuff, according to China Daily.

China’s deep underground ambitions might bring innovation to exploration but have been long preceded by actual mining in South Africa—although not without problems, as the country’s deplorable safety record shows. Greater depths bring greater threats from rockfalls and mini-earthquakes.

At 3.9 kilometres’ depth AngloGold Ashanti’s (NYSE:AU) Mponeng holds status as the world’s deepest mine. Five other mines within 50 kilometres of Johannesburg work from at least three kilometres’ depth, where “rock temperatures can reach 60 degrees Celsius, enough to fry an egg,” according to a Bloomberg article posted by

In his 2013 book Gold: The Race for the World’s Most Seductive Metal, Matthew Hart recounts a visit to Mponeng, where he’s told a “seismic event” shakes the mine 600 times a month.

Sometimes the quakes cause rockbursts, when rock explodes into a mining cavity and mows men down with a deadly spray of jagged rock. Sometimes a tremor causes a “fall of ground”—the term for a collapse. Some of the rockbursts had been so powerful that other countries, detecting the seismic signature, had suspected South Africa of testing a nuclear bomb.

AngloGold subjects job-seekers to a heat-endurance test, Hart explains.

In a special chamber, applicants perform step exercises while technicians monitor them. The test chamber is kept at a “wet” temperature of eighty-two degrees. The high humidity makes it feel like ninety-six. “We are trying to force the body’s thermoregulatory system to kick in,” said Zahan Eloff, an occupational health physician. “If your body cools itself efficiently, you are safe to go underground for a fourteen-day trial, and if that goes well, cleared to work.”

Clearly there’s more than technological challenges to mining the deeps.

By the way, credit for the world’s deepest drilling goes to Russia, which spent 24 years sinking the Kola Superdeep Bore Hole to 12,261 metres, halfway to the mantle. Work was halted by temperatures of 180 degrees Celsius.

This is the second of a two-part feature. See Part 1.

Dunnedin Ventures wraps up summer field work, expands Nunavut diamond property

October 4th, 2016

by Greg Klein | October 4, 2016

Encouraged by last year’s success, Dunnedin Ventures TSXV:DVI expanded both its till sampling program and property size at the Kahuna diamond project in Nunavut. On October 4 the company announced completion of 1,111 till samples, approximately 10 times the amount taken in 2015. Dunnedin also staked another 25,000 hectares, bringing the property size to around 60,000 hectares and its border within about 10 kilometres of Meliadine, where Agnico Eagle Mines TSX:AEM sees gold production potentially starting in 2020.

Dunnedin Ventures wraps up summer field work, expands Nunavut diamond property

Some diamonds from the Notch kimberlite
between 0.6 and 0.85 millimetres.

“Last year’s program effectively identified several new potentially diamond-bearing kimberlite pipe and dyke targets,” commented CEO Chris Taylor. “The much larger 2016 program was implemented to expand upon existing diamond indicator mineral trains and to identify additional prospective diamond sources through testing the down-ice mineral signatures of geophysically interpreted kimberlite pipes and dykes across the property.”

Dunnedin uses sampling techniques and proprietary mineral chemistry filters pioneered by company adviser Charles Fipke at his Ekati discovery. Additionally, samples from the previous year are being re-examined for possible gold content.

Meanwhile work continues on diamond recoveries from mini-bulk samples taken last year at the project’s PST and Kahuna kimberlites. Early last month the company reported that a 2.32-tonne sample from the Notch kimberlite revealed 85 commercial-sized stones totalling 1.95 carats.

Last year’s resource estimate showed a near-surface inferred category for the Notch and Kahuna kimberlites, 12 kilometres apart:

  • Kahuna (+0.85 mm cutoff): 3.06 million tonnes averaging 1.04 carats per tonne for 3.19 million carats
  • (+1.18 mm cutoff): 0.8 ct/t for 2.45 million carats

  • Notch (+0.85 mm cutoff): 921,000 tonnes averaging 0.9 ct/t for 829,000 carats
  • (+1.18 mm cutoff): 0.83 ct/t for 765,000 carats

  • Total (+0.85 mm cutoff): 3.99 million tonnes averaging 1.01 ct/t for 4.02 million carats
  • (+1.18 mm cutoff): 0.81 ct/t for 3.22 million carats

Both dykes remain open along strike and at depth. The resource didn’t include the PST kimberlite, where sample recovery showed 96 commercial-sized diamonds totalling 5.34 carats.

The property’s located about 25 kilometres from the Hudson Bay town of Rankin Inlet.

Read more about Dunnedin Ventures.

See Chris Berry’s report on long-term diamond demand.