Project Overview
The Little Butte Project is located in northwestern Arizona and consists of 7 patented and 101 unpatented mining claims covering a total of 2,160 acres. Located within the Plomosa Mining District, the property is 30 miles east of Parker, 21 miles northeast of the Copperstone Mine, and 80 miles south of the Moss Mine. Drilling in the project area has intercepted significant gold and copper. In response, this initial, internal resource estimate and Plan were prepared including bulk testing of gravity gold separation from high-grade veins.
Mineralization
While much of the historic drilling of the property has been for either high-grade gold/copper veins or sediment hosted gold across a large area of patented and unpatented lode claims, significant close-spaced grid drilling has also been conducted on a portion of the patented claims. The patented claims (100% owned by Great Basin (GB)) have the advantage of needing minimal permitting for exploration and production. GB has completed initial gold and copper metallurgy with favorable results. An initial internal resource has ‘just been compiled to determine what additional work is needed to begin production. This work would include some metallurgy on the iron resource which is closely associated with the gold and copper.
The area underlain by a minimum of +40 feet (12 meters) of >0.17ppm gold mineralization closely follows copper with a few exceptions. There is a distinct northwest trend to the copper/gold zone that is aligned with the identified high-grade veins. Note that the majority of drill holes have significant Au/Cu values. Continuity is best where east-west lines of holes were drilled 100 feet (30 meters) apart.
The cross section above shows copper grades greater than 0.1% extend from the surface down to 60 meters (200 feet). Higher grades, some over 1%, occur near high angle veins that often contain the higher gold values.
All mineralized rocks in the project area are highly weathered and copper has been largely mobilized to the top of the former water table.
Planned Development
The proposed exploration and development program at Little Butte should include 40-50 angle RC (reverse circulation) holes <300 feet (90 meters) deep on a 100 feet (30 meter) spaced grid. The holes would be drilled at a 45 degree angle due west following the existing drill pattern.
Two or three core holes for heap leach metallurgical work will be needed. Column testing using a course crush will be done for copper using sulfuric acid for core with low-grade gold values. The leached ore will then be cyanide leached to determine low grade gold recovery.
Using an excavator mounted with a percussion hammer, bulk sampling of high-grade veins will be used to verify high recoveries found in initial gravity separation tests. A crusher, pulverizer, and spiral gold recovery system will be utilized. If successful high-grade gold recovery will continue and may help fund the project.
A NI 43-101 reserve study will be completed when all drilling results are in hand. If the resource is significant a PEA (Preliminary Economic Assessment) will be written after all metallurgy is completed.
Although no significant permitting is required on patented claims in Arizona, an expanded resource to the northwest will require an NOI (Notice of Intent) be on the surrounding BLM ground. Examination of the water rights given when the property was patented is also needed to determine what is included.
In 2010, a Utah based company planned to ship specular hematite from western Utah to the west coast of the U.S. by rail, and then by ship to China. This venture failed for unknown reasons, possibly because there are no west coast ports that ship iron. The Fe grades for this venture were 58-62%. Exploration drilling at Little Butte has intersected several zones of +30% iron as specularite. However, the hematite at Little Butte will probably need upgrading by gravity beneficiation and magnetized roasting. A test of the feasibility of upgrading iron grades using drill cuttings is planned. If positive, iron may need to be included in the recovery flow sheet.
Great Basin Resources is seeking a partner to assist in moving the Little Butte project forward to production. The Company will consider a lease, option or JV agreement.