Location
Project Overview
Work Performed
Planned Exploration
Geology

Location

International Northair controls the Sierra Rosario silver/gold project located in the state of Sinaloa, Mexico.  The project is located approximately 25 linear kilometers northwest of Choix, Sinaloa; and 40 kilometers east of Alamos, Sonora.  Project access and infrastructure are reasonable. The property can be reached by driving approximately 45 minutes from Choix, followed by a four kilometer trail to the southern boundary of the concession.  Working conditions are excellent from September through June, with a rainy season from July through mid-September. Terrain is moderate with elevations ranging from about 600 to 1300 meters.

Overview

Sierra Rosario contains dozens of historic placer gold workings in numerous small drainages, as well as abundant gambusino workings in hard rock.  Northair staked the concessions in 2002 and, in early 2004, entered into an agreement with Sparton Resources Inc. where they can earn a 51% interest in the 1090 hectare property by paying Northair $130,000 (Cdn.) in cash, issuing 275,000 common shares and incurring $800,000 (Cdn.) in exploration expenditures over a four year period.  Spartan has completed an extensive geological, geochemical and geophysical work program which identified several excellent high grade silver-gold and base metal targets for drill testing.  Northair exploration staff discovered six gold and silver occurrences within the property previous to optioning to Sparton and additional zones have been defined by Sparton�s exploration.  The San Rafael gold-silver zone represents the highest priority mineralized features located so far on the concessions and Sparton is planning to drill this zone in 2007. 

Work Performed

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 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, geological mapping and geophysical survey program on the property.  Each of the 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 the three key areas of the property.  The magnetic and electrical surveys have 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 have tested a 500-metre-long portion of the 1.1-kilometre-long La Josca structure. The structure was intersected in all holes 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.  Additional mapping and trenching will be required to better establish geological controls for the gold mineralization.  

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 Spartons 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. 

Planned Exploration

Geology

Sierra Rosario contains basement rocks of Laramide age granodiorite overlain by weakly metamorphosed andesite belonging to the Lower Volcanic Complex. These rocks are overlain by Cretaceous massive limestone and calcareous sandstone, and younger rhyolite ignimbrite belonging to the Upper Volcanic Complex. Intrusive rocks consisting of intermediate porphyry dikes and a large intensely altered rhyolite porphyry are exposed at the San Rafael Zone.

In the San Rafael zone, both skarn and structurally controlled mineralization containing barite, copper, gold, and silver are present and values of up to 7.28% Cu and 13 g/t gold were obtained from samples taken from boulders in a gully below an old mine dump. Strong base/precious metal mineralization is located in a shear fracture zone east of the main rhyolite intrusive as well as in fault zones associated with rhyolite dykes in limestone on the east side of the property where there is a large multi element soil anomaly. 

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