The Silver District Property covers a portion of the historic Silver District in La Paz County, approximately 80 kilometres (50 miles) north of Yuma in southwest Arizona. Subject to third party net smelter royalties, Columbus controls a 100% interest in the Property.
Geology
The property covers a portion of a Precambrian metamorphic complex which is intruded by Cretaceous granite and diorite. The basement rocks are overlain by Miocene rhyolitic and andesitic volcanics which appear to coincide with the development of the faulting which host the silver-bearing veins of the district.
Three major fault systems traverse the property from south to north. The western structure strikes northwest, while the two eastern structures strike north and northwest respectively. Mineralized veins, which occur intermittently within the structures, contain quartz, calcite, fluorite, and barite with various silver, lead, and zinc minerals.
Past Work
Historical (19th Century) production totaled approximately 1.5 million ounces silver. Modern exploration was carried out between 1975 and 1992 by The New Jersey Zinc Company and Orbex Minerals and included extensive resource delineation drilling, metallurgical test work and feasibility studies.
Past programs delineated a historical resource of 3,820,000 tons grading 4.60 ounces per ton silver (+17,500,000 ounces) (3,464,000 tonnes at 157.7 g/t) plus potentially commercial fluorite, barite and zinc-lead in a number of deposits. Most of the identified resource occurs on Columbus Silver's claims and Columbus is pursuing negotiations to acquire additional claims to increase its interest in the historical resource. Past programs and studies indicate that the resource is potentially mineable in low strip ratio open pits and amenable to recovery by flotation followed by cyanidation. This historical resource is not NI 43-101 compliant and a qualified person has not done sufficient work to classify the historical estimate as a current mineral resource. It should not be relied upon and Columbus Silver does not treat it as a current mineral resource.
Planned Program
Three major vein systems, with collective strike lengths of approximately 13 kilometers (approx. 8 miles) provide good potential for resource expansion. An exploration program to expand the resource base, followed by an economic scoping study to update past feasibility studies based on current conditions, is required at Silver District.
