Luna Gold Corp. (TSXV-LGC) has provided an update on exploration activities at its Cachoeira gold project including results of extensive auger drilling and surface channel sampling programs at the Coruja and Arara targets located to the north of the Tucano deposit within the Cachoeira Shear Zone.
750 meter long mineralized quartz vein system averaging 1.5 meters wide defined at Coruja via surface channel sampling including:
- 8.07 meters @ 3.17 g/t Au including 1.01 meters @ 17.01 g/t Au in channel OC-51 along vein
- 5.07 meters @ 4.42 g/t Au and 10.83 meters @ 3.24 g/t Au including 4.04 meters @ 7.68 g/t Au in channel OC-52 along vein
- 1.96 meters @ 11.64 g/t Au and 4.70 meters @ 5.40 g/t Au in channel OC-92 along vein
Surface oxide mineralization defined via auger drilling program at Coruja including:
- 7.00 meters @ 4.77 g/t Au including 1.00 meter @ 23.00 g/t Au and 5.00 meters @ 1.68 g/t Au in auger hole TX0353
- 7.00 meters @ 1.06 g/t Au in auger hole TX0368
- 3.00 meters @ 2.25 g/t Au in auger hole TX0331
Surface oxide mineralization defined via auger drilling program at Arara including:
- 4.50 meters @ 1.30 g/t Au in auger hole TX0271
- 6.60 meters @ 21.83 g/t Au including 1.60 meter @ 88.28 g/t Au in auger hole TX0291
Luna's President & CEO, John Blake, comments, "These ongoing results continue to unlock upside potential and increased confidence in the Cachoeira deposit. These results combined with those previously drilled, are being incorporated into a maiden NI 43-101 mineral resource estimate to be released in December 2010 for the Cachoeira Gold Project.
Luna Gold will continue with exploration at Cachoeira and at Aurizona to pursue further resource development in the Company's highly prospective landholding in this mining friendly region of Brazil."
The Coruja target is located in the central portion of the Cachoeira Shear Zone (CSZ) and consists of a narrow, steeply dipping shear zone which hosts a mineralized quartz vein system that outcrops intermittently over a 750 meter strike length. The vein set is quite continuous though pinches and swells locally along strike and down dip. Wall rock to the quartz vein is locally albitized and silicified. Average width of the main vein at surface is 1.50 meters though it locally attains widths of up to 4 meters. Mineralization is associated with a high resistivity anomaly within areas of moderate to strong IP response consistent with quartz veining at depth. Wide-spaced drilling at Coruja has cut several zones of high-grade quartz veins including Luna drilling in 2008 which intersected 20.00 meters @ 9.04 g/t Au including 6.00 meters @ 27.72 g/t Au in hole LCD017 from 33 meters core depth though this does not represent true thickness (Luna press release September 08, 2008). Additional drilling is required to better define the plunge of the high-grade quartz veins.
Surface Channel Sampling Program
A channel sampling program was conducted across all suitable surface vein and wall rock outcrops at Coruja. 1,086 meters of sampling (1197 individual samples including QA/QC) was completed. Detailed mapping was conducted along the channels and the data have been integrated into the geologic model. The program identified several zones of both low- and high-grade outcropping mineralization which collectively define a significant gold-bearing quartz vein system.
Auger Drill Program
An auger drill program totaling 2,064 meters (2,253 individual samples including QA/QC) in 166 holes was conducted at the Coruja target to identify oxide gold mineralization and provide supplementary drill data for resource estimation purposes. Holes were drilled on a regular 100x25 meter section grid to 15 meters depth. In some cases planned depth was not achieved due to difficult ground conditions. Average hole depth for the program is 12.40 meters. The program has identified an oxide mineralized zone over the Coruja target spatially associated with the extensive outcropping mineralized quartz vein system described above.
Arara is the most northerly target defined to date at Cachoeira and has been drilled by CCO (1988), Vale (2003) and more recently by Luna in 2008. It is located within the northern portion of the CSZ and consists of a zone of lower-grade gold mineralization extending for 500 meters strike length in a north-northeasterly direction. Luna drilling in 2008 intersected zones of both low and high-grade mineralization including 97.00 meters @ 0.43 g/t Au from surface in hole LCD001 and 6.00 meters @ 12.58 g/t Au in hole LCD009 from 164 m core depth (Luna press release June 26, 2008).
Surface Channel Sampling Program
Surface exposure is poor at Arara and a limited channel sampling program was conducted across all suitable surface outcrops. 175 meters of sampling (207 individual samples including QA/QC) was completed in seven separate channels. Detailed mapping was conducted along the channels and data integrated into the geologic model. The program identified several zones of low-grade outcropping mineralization with a best interval of 41.87 meters @ 0.68 g/t Au. Assay values for surface channels not reported here range between below detection limit (<0.05 g/t Au) to 4.89 g/t Au.
Auger Drill Program
An auger drill program totaling 1293 meters (1,419 individual samples including QA/QC) in 101 holes was conducted at the Arara target to determine the extent of oxide gold mineralization and provide supplementary drill data for resource estimation purposes. Holes were drilled on a regular 50x25 meter section grid to 15 meters depth. In some cases planned depth was not achieved due to difficult ground conditions. Average hole depth for the program is 12.80 meters. The program has confirmed a low grade oxide mineralized zone over the Arara target. One very high-grade intercept associated with quartz veining was drilled in hole TX0291, however this interval is not representative of mineralization intersected in the auger drill program.
Assaying of Historic Drill Core
Resampling of Vale drill core from Arara was conducted as part of the Arara data validation process. 174 samples (including QA/QC samples) from nine drill holes were assayed representing continuous core intervals of low- and high-grade gold mineralization totaling 157 meters. Mean sample length is 1 meter. Luna re-sampling followed the original Vale sample intervals and were composited to facilitate comparison with Vale data.
Luna's VP Exploration, Titus Haggan, comments, "The results of Luna's exploration programs at Coruja and Arara have added significantly to our understanding of the geology and gold mineralization at these targets. In particular the systematic sampling of the extensive outcropping quartz vein at Coruja combined with re-analysis of drill data has enabled understanding on structural controls and grade distribution at Coruja. This target has seen only reconnaissance scale drilling to shallow depths and requires significant additional drilling to define the extent of the quartz vein mineralization. Mineralization at Arara consists of a combination of lower-grade near surface oxide mineralization and high-grade mineralization hosted in quartz vein sets."
Cachoeira is an advanced stage gold project in northeast Pará state, Brazil. Orogenic gold mineralization occurs within a 5 km long north trending shear zone. Three targets, Tucano, Coruja and Arara, have been defined to date. The Tucano deposit is located within the Cachoeira town urban limit.
Source: Luna Gold Corp.