Triton Mining looks to Argentina for growth

While its top priority continues to be expansion of the Limon gold mine in Nicaragua, Triton Mining (TSE) is also busy establishing a presence in Argentina.

The country, which has been described as South America’s “last mining frontier,” went largely unexplored over the past 50 years, largely on account of its turbulent political history.

That was then, and this is now.

With a stable democratic government now in place and economic reforms (including revised mining policies) beginning to bear fruit, the opportunity for foreign investment has never been better.

Through a joint venture with Minera Aconcagua, a wholly owned subsidiary of Northern Orion Exploration (VSE), Triton holds a half interest in nine properties scattered throughout Argentina. Apart from these, the company holds a full interest in the 2,500-hectare Incachule project in Salta province and has opened an office in the city of the same name. To date, Triton has sought permission to explore 33 cateos (or claim blocks) within the provinces of Salta, Jujuy, Catamarca, Rio Negro and Santa Cruz.

During a recent visit, The Northern Miner toured the Incachule property and two of the joint-ventured projects, namely Incahuasi and Organullo. The three properties, nestled in the Andes mountain range in the country’s northwest, are undergoing reverse-circulation drilling to determine their potential for hosting epithermal-style gold mineralization.

Accessible by dirt roads which wind through mountainous terrain at elevations of up to 4,500 metres above sea level, the properties lie in an area of rolling plains interspersed with low-lying salars (salt flats) and moderately sloping ranges with local relief in the order of 450 metres.

Incachule

The Incachule project is 32 road km west of San Antonio de los Cobres, a small railway town. The city of Salta lies 140 km to the southeast.

An 8-to-10-hole program, consisting of up to 1,300 metres of drilling, is attempting to confirm that the prospect has the makings of an epithermal deposit. Large areas of argillic and siliceous altered dacite are mineralized by disseminated, low-grade gold and antimony.

The property is underlain by a basement of Precambrian metasediments and covered by Tertiary volcanics. The package of rocks is sliced by major, crosscutting, tectonic features that trace into neighboring Chile.

Within an area measuring 1.6 by 1.8 km, at least five principal structures have been outlined. These have a vertical orientation and trend in a northwesterly direction with a strike length exceeding 500 metres.

The altered zones consist of quartz stockwork systems with widths of up to 80 metres. Surface sampling has returned values of 1 to 2 grams gold per tonne for individual veins and 0.25 to 0.5 gram for the stockwork.

David Jenkins, Triton’s vice-president of exploration, believes the low gold values at surface indicate that the property is on the outer limits of a larger epithermal gold system and that these values will increase at depth. He adds that the presence of many stages of silicification and brecciation, along with sulphides and sericitic alteration, bodes well for exploration. Also, the fact that active hot springs occur on the southeastern portion of the property indicates the existence of an underlying epithermal system.

The property was worked during the 1950s and 1960s for antimony, producing 3% to 4% stibnite from individual veins occurring at a much lower level of the deposit. Further exploration during the early 1970s continued to focus on exploration for high-grade antimony. Jenkins notes there is a record of a previous sample from one of the antimony veins (the Victoria), which assayed 13 grams gold.

The preliminary drilling will be carried out across the property in an attempt to identify the level at which high-grade gold occurs.

Organullo

Twenty kilometres distant from the Incachule lies the joint-ventured Oganullo project. The 2,500-hectare property was worked for bismuth-gold in the early 1930s, when several adits were driven on two narrow quartz veins within a main zone of mineralized, brecciated, quartz stockwork veining.

Triton carried out geochemical sampling and outlined an alteration system in the Precambrian sediments. Anomalous gold values occurring in a wedge-shaped area measure almost 5 km in length and vary in width from 100 to 1,000 metres.

Initially, 3,000 metres will be drilled, most of which will focus on the higher-grade areas of the geochemical anomaly. An additional 2,000 metres will be added if results are warranted.

Incahuasi

Also advanced to the drilling stage is the 239-hectare Incahuasi project, which lies within the province of Catamarca, close to a lithium-mining operation of FMC.

Sporadic gold production has been traced from the 1700s up until the 1950s. Between 1936 and 1954, 77,000 tonnes averaging 17 grams were mined from a principal quartz vein by underground methods to a depth of 150 metres and over a strike length of 400 metres.

A series of large veins, fractured systems and altered quartz stockwork systems measuring up to 100 metres in width lie within a package of weakly metamorphosed sediments consisting of phyllites, greywackes and sandstones. Surface geochemical sampling has returned peak gold values of up to 4 grams.

Jenkins believes Incahuasi has experienced extensive leaching of gold from surface as caused by wind-blown salts from the adjacent salt plains. With 2,000 metres of drilling planned, he expects this theory will be verified by the discovery of increasing gold values at depth.

Argentina shares some 3,000 km of the Andean Cordillera with Chile, and thus both countries share a similar potential for epithermal and porphyry-hosted deposits. Exploration companies working in the Cordillera continue to make use of satellite photo imagery, which enables them to zero in on alteration zones.

Cateos

As previously mentioned, Triton has applied for work permits for 33 cateos, which range in size from 1,000 to 20,000 hectares. Accessibility by road is a crucial factor in Triton’s criteria for selecting properties, in addition to extensive research. In searching for potential epithermal gold targets, the company scours old church and mining records dating back to the 1800s.

The company is following up with field visits to the cateos for the purpose of taking preliminary samples. Several companies have expressed interest in forming joint ventures on one or more of the claim blocks.

El Limon

Meanwhile, back in Nicaragua at Triton’s El Limon mine, a US$6.4-million expansion project is nearing completion. A new 1,100-ton-per-day mill is officially slated for startup by the end of September, but management feels the semi-autogenous-grinding ball mill and crusher grinding circuit may be up and running by late August.

The mill is expected to produce more than 50,000 oz. gold per year at a cash operating cost of roughly US$200 per oz. During the first half of this year, Triton produced 11,837 oz. at a direct cash cost of US$250 per oz. To provide sufficient feed for the new mill, the company accelerated development of its underground workings, allowing for simultaneous production from at least three headings. This increased development is reported to have added substantial costs to the direct cash cost.

Drilling on the Santa Emilia Oeste deposit continues to step out towards the underground workings of the Talavera. Proven and probable reserves have increased to 209,000 tons grading 0.24 oz., while minable reserves, at the Talavera deposit, remain at 1.4 million tons grading 0.17 oz.

Trenching continues at the Tigre deposit, which is north of, and contiguous with, the North open pit. Drilling will begin shortly in an effort to firm up sufficient reserves for an open-pit operation.

Jenkins notes there is a backlog of close to 5,000 samples awaiting assaying from exploration carried out regionally and within the Limon mine district. To alleviate this problem, he is shipping some 3,000 samples to Vancouver for processing.