Advanced Stage Tungsten Project
Presentation Tabuaço Tungsten Project
The Tabuaço Experimental Mining Licence (EML) in North-Eastern Portugal covers a total area of 45.13 km², and has been granted to Colt following, and as a consequence of, the exploration project undertaken by the company at its Armamar-Meda exploration concession between 2007 and 2012. It is located 300 km north, north-east of Lisbon, 100 km to the east south-east of Porto and 25 km to the south-east from Peso da Régua. Surrounding towns include: Armamar, Moimenta da Beira, Penedono, S. João da Pesqueira and Tabuaço. The EML encloses the Tabuaço skarn-type tungsten (scheelite) deposits, which include the São Pedro das Águias (SPA) and Aveleira tungsten resource areas,and the adjacent exploration targets of the SPA-Aveleira Gap, the Quintã-Távora zone, as well as on the East bank of the Távora river.
Since acquiring the exploration rights over this area in late 2007, as part of its Armamar-Meda exploration concession, Colt carried out extensive outcrop sampling work, and then embarked on an exploration and evaluation diamond drilling program which to date involved in excess of 100 drill holes, totalling more than 11,400 metres.
A portion of the deposit underlies a port wine vineyard on the western terraced slope of the Távora River valley. Though surface rights are subordinate to mining rights, often exploration and development activities are hampered by delays imposed by land owners. Therefore, in August 2011, Colt Resources acquired 140 hectares of surface rights, which includes a vineyard and operational winery producing Senhora do Convento port and red table wines, along with a former Cistercian monastery. By securing the land over the majority of the deposit area, the company has unencumbered access to the most of the project area during the drilling program. In addition, the land is suitable for the entrance to the planned underground mine. Additional acreage will be required to accommodate the mine’s infrastructure upon development, specifically for the mine tailings disposal facility and tungsten ore concentrator plant; however, management plans to procure a site within three kilometers of the proposed mine entrance.
Preliminary Economic Assessment (PEA)
Positive PEA was completed in September 2013. See full PEA in the Report section. The study delivered a post-tax NPV5% of $67.4m and IRR of 30.7%. Read the September 4th, 2013 Press Release here.
NI 43-101 Resource Estimates
November 2011 – Indicated Mineral Resources
- Tonnage (thousand tones) : 760
- Grade (% WO3): 0.58
- Contained Metal (MTU* WO3): 440,000
November 2011 – Inferred Mineral Resources
- Tonnage (thousand tones): 1,330
- Grade (% WO3): 0.57
- Contained Metal (MTU* WO3): 760,000
October 2012 – Indicated Mineral Resources
- Tonnage (thousand tones) : 1,495
- Grade (% WO3): 0.55
- Contained Metal (MTU* WO3): 815,000
October 2012 – Inferred Mineral Resources
- Tonnage (thousand tones): 1,230
- Grade (% WO3): 0.59
- Contained Metal (MTU* WO3): 720,000
Tabuaco/Aveleira Tungsten Project Resource Highlights (0.3% WO3 Cut-off Grade)
* The term “MTU” is an abbreviation for one “Metric Tonne Unit” and is equal to 10Kg of material.
- October 3rd, 2012: Updated NI 43-101 Resource Estimate for Colts 100% Tabuaço Tungsten Project, Northern Portugal
- November 7th, 2011: Initial NI 43-101 Resource Estimate for its 100% Tabuaço Tungsten Project, Northern Portugal
Classification of the Mineral Resource is based on quality control data, geological continuity and borehole spacing. The estimate is considered to have reasonable prospects for eventual economic extraction, as it is constrained by a cut-off grade derived from reasonable underground mining and processing costs;
- A cut off grade of 0.3% WO3 has been used to constrain the Mineral Resource estimate;
- This cut-off grade is based on a WO3 price of US$300/mtu2, an underground mining cost of US$30/t and a processing cost of US$22/t, as supplied by SRK Denver, and agreed by Colt Resources;
- The deposit remains open in all directions.
Geologic work carried out to date at the Tabuaço area of the Armamar-Meda concession has identified scheelite mineralized skarn horizons along the western slope of the river Távora that display potential to host a significant mining operation. These mineralized skarn horizons occur as locally well-exposed outcrops, discontinuous outcrop clusters, and float extending for a total strike length of around 1.7 km from the Quinta das Herédias zone in the SE to the Quintã-Távora slope area in the NW (Figure 2).
At least one main horizon and possibly two lower horizons have been noted. Where well-exposed, the main skarn horizon is mostly flat lying to gently dipping, 5º to 25º, and ranges in width from 5 m to 20 m. The extent of these horizons remains open along strike beyond the Quintã-Távora Zone to the northwest and at depth.
The main skarn horizon in the São Pedro das Águias area exhibits the best exposure, largest width, greatest strike continuity, and highest tungsten grades in the Tabuaço area. Outcrop sampling by Colt indicates the main horizon has an average surface grade of 0.673% WO3. Several outcrop channel samples show grades greater than 1% WO3. Historic shallow drilling of the main horizon produced drill results grading as high as 1.180% WO3 over an interval of 19.35 m.
Due to soil cover, extensions of the São Pedro das Águias main horizon up to the Quintã-Távora Zone, a strike length of nearly 1 km, as well as recently discovered skarns zones located some 50 to 60 m below the São Pedro das Águias main horizon, remain poorly explored and have never been drill tested. These zones greatly add to the potential of the area.
In 1981 and 1982, following drilling on the São Pedro das Águias main horizon, SPE-SEREM estimated a potential geologic resource* of about 1 million tonnes with an average grade of 0.87% WO3 (Note: geologic resource is not compliant with NI 43-101 standards). This estimation was very preliminary being based on results from a few shallow drill holes and channel sampling. Grade estimation used blocks grading between 0.63 and 1.06% WO3. The areal extent of this historical resource estimation was less than 300 m by 180 m: this covers less than half of the potential area of the main skarn horizon at São Pedro das Águias.
*Note: The historical resource is based on very limited drilling. A qualified person has not done sufficient work to classify the historical estimate as current mineral resources or mineral reserves. The company is not treating the historical estimate as current mineral resources or mineral reserves. The historical estimate should not be relied upon.
- Awarded Experimental Mining License: Tabuaço EML
- Receives positive metallurgical results from testwork performed on representative samples taken from the Tabuaço Tungsten Project
- Updated NI 43-101 Resource Estimate for Colt’s 100% Tabuaço Tungsten Project
- Submits the Initial NI 43-101 Resource Estimate for its 100% Tabuaço Tungsten Project
- Completes Acquisition of Key Surface Rights for its Tabuaço Tungsten Project
- Announces Definition Drilling Program on the Tabuaço Tungsten Project
- Announces Metallurgical Program for the Tabuaço Tungsten Project
- Production of NI 43-101 Technical Reports for Portugal properties
- Colt Acquires the Concession
- Exploration in the Tabuaço Area and at São Pedro das Águias deposit.
- Tungsten occurrences were initially discovered along the Távora River in the 1970s by government geologists.
- Small artisan tin mines located in the opposite margin of the Távora River.
- Q3 2012 Advanced Deposit Modeling – completed
- Q4 2012 NI43-101 Resources Estimate – completed
- Q3 2013 Preliminary Economic Analysis – completed (PR September 4th, 2013)
- Q2 2015 NI43-101 Resources Update
- Q4 2015 Bankable Feasibility Study / Full Mine Permitting
- Q1 2016 Construction
- 2017 Production
Tabuaço Next Steps
- As part of its experimental mining work program, Colt will proceed with the excavation of both an access adit and a vertical shaft into the São Pedro das Águias deposit, for the purpose of testing the proposed mining method, gathering further information on the rock mechanical conditions, and extracting a bulk sample for pilot ore concentration work.
- Surface diamond drilling program will be continued to explore and evaluate the above referred deposits and exploration zones.
- Drilling, during the 2013 and during 2014, will be expanded, to test the area between Aveleira and Tabuaço where initial results have indicated the presence of tungsten mineralization. Colt will also continue to test other prospects in the region within Colt’s 100% controlled exploration concession.
- Environmental impact studies will continue so as to optimize the mining and processing facilities and minimize their environmental impact.
- Geotechnical drilling will be performed to test ground conditions along potential underground access routes.
- Bulk samples will be collected so as to allow more detailed metallurgical testwork to improve recoveries and assist in designing optimal processing methods.
- A Preliminary Economic Assessment and Tabuaço/Aveleira was concluded during the third quarter of 2013.