TORONTO (miningweekly.com) – Canadian mining exploration and development company Colt Resources on Wednesday received two mining licences and two exploration licences for its Portuguese projects.

The company said an official signing ceremony was held at the company's fully owned Tabuaço tungsten project, for which the Tabuaço experimental mining licence (EML) was awarded. The EML covers a total area of 45.13 km² in north-eastern Portugal, and had been granted to Colt following the exploration project undertaken by the company at its Armamar-Meda exploration concession between 2007 and 2012.

Since acquiring the exploration rights over this area in late 2007, Colt carried out extensive outcrop sampling work, and then embarked on an exploration and evaluation diamond drilling programme, which to date involved in excess of 100 drill holes totalling more than 11 400 m.

The most recent National Instrument 43-101-compliant resource statement issued by Colt for the Tabuaço tungsten deposits reported indicated mineral resources of 1.49-million tons grading 0.55% tungsten trioxide (WO₃) containing 815 000 metric ton units (MTUs), equal to 10 kg of contained WO₃, and inferred resources of 1.23-million tons grading 0.59% WO₃ containing 720 000 MTUs from the São Pedro das Águias and Aveleira deposits.

Colt believed the deposit to have good potential for expansion.

As part of its experimental mining work programme, Colt would excavate an access adit and a vertical shaft into the São Pedro das Águias deposit, to test the proposed mining method, gathering further information on the rock mechanical conditions, and extracting a bulk sample for pilot ore concentration work. The surface diamond drilling programme would also continue to explore and evaluate the deposits and exploration zones.

Further, Colt said it had also received the Santo António EML, which covers a total area of 35.34 km².

This concession was granted to a joint venture (JV) between Colt and Brazilian company, Contecnica, in which Contecnica would be the operator.

The granting of this concession follows on the exploration project undertaken by Colt in the Penedono concession between 2007 and 2012.

Mining activity in the area dates back to Roman times, when gold was produced from Santo António, Ferronha and Dacotim. Small-scale artisanal tungsten (wolframite) mining took place in the area during the 1940s and 1950s. Gold mining attempts were also undertaken in the mid-twentieth century from Ferronha, Dacotim and particularly Santo António. The latter was exploited by the Companhia das Minas de Ouro de Penedono in the 1950s, having produced a total of around 11 000 oz of gold from a total of 105 000 t of ore extracted from underground mining along veins two and three, and to a minor extent veins 7 and 13.

The 1950s Santo António mining plant never achieved an acceptable level of gold recovery and as a result the 100 000 m³ of tailings material still at the Santo António mine are believed to host gold that may be recoverable using more modern methods.

During the experimental mining period the JV’s activity would focus on trial openpit mining at Turgueira, recovery of gold from the Santo António tailings, the excavation of a new adit to access and dewater the Santo António underground workings, and the recovery of blasted ore left in the old galleries for pilot metallurgical testwork and continuing evaluation drilling of the vein deposits.

Meanwhile, the company also received two exploration licences, one for the Borba copper/gold project in central-eastern Portugal, which covers a total area of 636 km², and one for the Cercal gold exploration project, located in coastal Alentejo province, in southern Portugal.

Colt is also developing the advanced-stage Montemor gold project, in southern Portugal.