The Sleitat Property is located in southwestern Alaska, 415 kilometers southwest of Anchorage. The property lies 130 kilometers west-northwest of lliamna and 35 kilometers north-northeast of Koliganek.


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The property is centered on the highest point along a 20 kilometer long, northeast trending set of bedrock hills, which rise to an elevation of 603 meters, roughly 500 meters above the extensive surrounding lowland plains. Vegetation on the hills is limited to tundra grasses and lichen.
The property was first discovered in 1983 by a Joint Venture of Cominco American Inc. and Enstar Resources Corporation, during a regional exploration program for Bolivian-style tin deposits. The Cass 1 to Cass 72 claims were staked to cover a complex granitic intrusion hosting sheeted greisen zones mineralized with cassiterite. The Joint Venture tested the property in 1983, 1984 and 1988 with moderate scale work programs that included mapping, geochemical sampling, geophysics and diamond drilling (9 holes totaling 723.8 meters). Their work defined interesting amounts of low to medium grade cassiterite-silver mineralization, and a limited but significant amount of coarse, high grade, vein hosted cassiterite in breccia zones.


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In 1989 the United States Bureau of Mines (USBM) evaluated the tin potential of the property, and INFERRED A RESOURCE of 25.9 million tons grading 0.22% - 0.37% tin, 0.04% tungsten, and 17 g/t silver.

Sleitat is dominated by an isolated, 40 hectare tin-tungsten-silver bearing Tertiary multi-phased granitic stock that intrudes a flysch sequence of Cretaceous Kuskokwim Group sandstones and shales. The property overlies the southern fault strand of the regional scale, NE trending, 4 km wide Mulchatna Graben. The stock is considered to be the southwestern-most of a string of similarly isolated Tertiary granite hosted greisen tin deposits in Alaska.

Strong greisen alteration extends across all of the main granite units and into the surrounding hornfelsed sediments, in closely spaced, sub-parallel, east-west trending and vertically dipping tabular bodies. Individual greisen bands vary in thickness from a few centimeters to 6 m in width, and are separated by both altered and unaltered granite. Two main greisen zones were initially identified by Cominco, the North Zone (900 m by 300 m) and the less densely banded South Zone (400 m by 250 m). The North Zone is now known to extend southwards beneath a thin cover of muscovite granite, is currently open to the south and at depth, and appears to be increasing in grade southwards.

Sleitat greisens primarily consist of fine-grained quartz and topaz with lesser white mica and disseminated blue-green tourmaline. Open spaced voids with clay are common in intense greisen altered zones, where feldspar and phyllosilicate minerals have been destroyed and partially replaced by quartz, topaz, white mica and tourmaline. Iron oxide and arsenic oxide staining are present, suggesting that the greisens once hosted minor sulphides.

Sleitat is primarily a tin-silver occurrence. The tin mineralization mainly occurs as cassiterite in all granitic units and in the surrounding hornfels. The best cassiterite is coarse grained and occurs along veins within breccia zones. The source of the silver values has not been identified, but it likely occurs as silver sulphosalts or as fine native silver inclusions.

Primary metallic minerals present at Sleitat are: Cassiterite, Sphalerite, Arsenopyrite, Wolframite and Pyrite. Accessory minerals present include: Stannite, Bornite, Chalcopyrite, Bismite, Bismuth-Arsenic compounds, and Ferrotantalite.


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• The occurrence is very well structurally prepared, and is associated with a robust altering and mineralizing greisen event (tin-silver rich). The structural development appears due to movement along the south limb of the major NE trending Mulchatna Graben Fault, which cuts through the centre of the Sleitat stock.
• Existence of ore grade Sn-Ag intersections (>0.3% Sn - often as coarse grained cassiterite) in some drill holes.
• Existence of high grade Sn-Ag in breccia (Cass 84-06: 6.7 m grading 4.8% Sn and 56.8 g/t Ag) which likely formed at the junction of intersecting faults and fracture zones. The intersection of the Mulchatna Graben Fault with the postulated NW Fault (at 607,105 m E and 6,657,933 m N - Nad 83, Zone 4) could represent an area where significant additional quantities of mineralized breccia will be defined.
• Attractive mineralization and greisen alteration intersected by the 2006 Brett drilling in Cass 06-10 and Cass 06-11, which is open to the south and to depth, and appears to be increasing in grade. It is thought that this mineralized trend may continue southwards up to and past the trace of the NE trending Mulchatna Graben Fault, which occurs 200m south of these two holes.
• Abundance of large untested areas lying within zones of good potential. The centre of the property constitutes one such area, while the South Greisen Zone constitutes another.

Solomon Resources Limited and Brett Resources Inc. are in the process of forming a Joint Venture to further the exploration of the Sleitat Mountain Tin Project in the 2009 exploration season.