Northair's field programs concentrated primarily in the San Rafael Zone which contains strong epithermal silver with gold mineralization within an intensely altered rhyolite porphyry having a surface expression of approximately 200 by 70 metres. First phase mapping and sampling by Northair in 2003 within the San Rafael Zone returned an average of 181 g/t silver and 0.321 g/t gold from 23 chip channel samples.
Sparton's ongoing field program confirmed Northair's exploration results, and indicated that Sierra Rosario contains numerous mineralized zones. In the fall of 2005, Sparton completed a sampling and geological mapping and program over the property as well as a geophysical survey over selected targets. Each three separate zones of mineralization explored by Sparton, referred to as La Josca, Las Tahunas and San Rafael, are areas of historical production from small underground and open cut excavations. The analytical results confirmed the presence of high grade gold, base metal and silver mineralization in these three areas of the property and magnetic and electrical surveys established distinct geophysical signatures for the mineralization in each area. In June 2006 Sparton completed a seven hole drill program to test high priority targets in the La Josca Zone. The holes tested a 500-metre-long portion of the 1.1-kilometre-long La Josca structure with the best results of 2.62 g/t gold over a one-metre core length in hole 7 and 1.12 g/t gold over a one-metre core length in hole 3.
The San Rafael Zone is the principal target area on the property and the geophysical work, in particular the magnetic survey, delineated a well defined magnetic anomaly associated with the San Rafael rhyolite porphyry body and also located a similar anomaly which is covered by upper volcanic series tuffs and may represent a new buried intrusion. After reviewing the results of Sparton's exploration programs, the Company and Sparton filed an application to increase the size of the claim holdings by 590 hectares to 1,090 hectares. The new claim area covers the extensions of the San Rafael Zone indicated by the geophysical surveys which now appear to be substantially larger than initially estimated. The new holdings may host both skarn type carbonate replacement deposits as well as the extensions of the known vein-structure hosted mineralization.
In 2008, an access road was constructed to the San Rafael Zone that allowed mechanical trenching to be completed. A total of 321 samples were taken in 20 sample lines from outcrops in roads and trenches throughout the zone with highlights of the trenching program including 34.8 metres of 192 g/t silver with 0.22 g/t gold; and 27 metres of 91.8 g/t silver with 0.15 g/t gold. There appears to be excellent potential the San Rafael Zone to be far more extensive than the present surface exposure and drilling will be required to establish the grades and geometry of the intrusive at depth.
Last:
$0.07
High:
$0.07
Low:
$0.07
Chg:
+0.01
Vol:
27200
