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| | |  43-101 Report Mexivada's Jefferson property comprises a contiguous block of 48 unpatented lode mining claims, totaling approximately 950 acres, that are owned or under option to the company. There are five small patented claims located inside the Jefferson property that are controlled by Round Mountain Gold Company (Barrick-Kinross JV). Mexivada. The Jefferson property covers the Jefferson Canyon gold-silver mining district, located 50 miles north-northwest of Tonopah and three miles east of Round Mountain, on the western edge of the Toquima Range in moderately rugged grass-, shrub-, and sagebrush-covered mountainous desert. Elevations on the property range between 7,160 feet and 8,600 feet. The climate is favorable for year round mining, with all the people, supplies and services needed for successful exploration and mining programs available in the area nearby. The Jefferson property is situated along the Round Mountain-Northumberland Gold Trend, an Oligocene- to Miocene-age structural zone that hosts the Barrick/Kinross' +12,000,000 ounce Round Mountain Mine and the nearby Gold Hill gold mine and Fronteer Development Group's Northumberland Mine, a Carlin-type, open pitted former gold producing mine. The Jefferson Canyon mining district was mined for silver and gold beginning in the late 1870's, and was explored by drilling by Echo Bay and its predecessor companies in the mid 1980's. It has since lain dormant of any exploration, until the arrival of Mexivada, which has conducted an extensive exploration program in 2005 and 2006, laying the foundation for renewed drilling of gold, silver and tellurium targets. Mexivada feels that the Jefferson Property holds good potential to host a new gold-silver-tellurium mine, with the delineation of several new open pit and underground mine targets. In the mid 1870s, eight mines were operating along the northwest-trending Prussian vein system, producing over ten thousand tons of high-grade gold-silver ores. Significant exploration work has been carried out on the Jefferson property since 1970, including rock sampling, diamond drilling, and early-stage exploration by such world class geologists as John Prochnau, a Doug Casey Research Hall-of-Fame explorer. In the early 1980s, drilling by Copper Range Exploration delineated two mineralized zones "Pit A" and "Pit B". The "Pit A" zone was reported to contain 10.5 million tons of mineralization grading 0.007 ounces per ton (opt) gold and 1.48 opt silver (0.24 g/tonne gold and 50.7 g/tonne silver). The "Pit B" Zone was reported to contain 3.7 million tons of mineralization grading 0.02 opt gold and 0.13 opt silver (0.69 g/tonne gold and 4.46 g/tonne silver). The gold grade appears to improve eastward on the Property from the Prussian vein workings toward Mexivada's SG-1 target area (see Figures below). These drill-indicated bodies of silver-gold mineralization in the "Pit A" and "Pit B" target areas at Jefferson were defined and quantified before the advent of National Instrument 43-101 , and Mexivada was not able to obtain a complete database of this early work on the Jefferson Property, so the calculations quoted above are not compliant with NI 43-101 and should not be relied upon. The local geology consists of thrust-deformed, lightly metamorphosed Paleozoic sedimentary rocks cut by Cretaceous, Eocene (Carlin-age) and younger Tertiary igneous intrusions, and capped by ash-flow tuffs of Tertiary ages, similar to the nearby Round Mountain and Gold Hill mines. Several generations of faults cut all of these rocks, and most of the silver and gold mineralization mined here in the past was controlled by these faults. Some disseminated silver mineralization also is present, as defined by the Copper Range drilling. The volcanic tuffs were deposited in the depression created when the several calderas in the Mt. Jefferson area formed. The bounding, northwest-trending Jefferson Canyon fault, which hosts the gold- and silver mineralized Prussian vein system at Jefferson, is thought to mark the southern margin of the calderas. Jefferson Canyon is a major, west-northwest trending continental structural boundary that was re-activated several times by faulting, providing repeated open spaces that were later host to episodes of mineralization. Cretaceous mesozonal "tombstone" granites form the south buttress/boundary on the south side of the Jefferson Canyon Fault (see figures below). Several episodes of mineralization were localized in and near this major boundary, in different rock types. Modeling of gravity data indicates several significant fault structures, one parallel to the Jefferson Canyon fault but situated approximately one kilometre to the northeast, which are interpreted to control certain alteration and possibly be related to gold and silver feeder structures beneath Porphyry Hill. Also present is a major north-northeast trending structure in Porphyry Hill that appears to have controlled certain gold-silver mineralization. Mexivada has conducted several "high-tech" geophysical surveys at its Jefferson property in the Round Mountain area, including airborne and ground magnetics, CSAMT, and high-density ground gravity, which were interpreted to indicate hydrothermal alteration related to felsic porphyry intrusions of Carlin- and younger ages, veining/alteration, and possible earlier base metal skarn and porphyry. Correlations with historic mine workings suggest that the non-skarn alteration is related to gold and silver mineralization. Pyrite-chalcopyrite mineralization has been found on mine dumps from the old, Prussian underground workings at depth, possibly verifying the presence of a pre-gold skarn/porphyry type mineralization event in the central part of the property in the "Porphyry Hill" target area. A major silver mineralization event occurred next at Jefferson, which provided the orebodies for mining in the 1870s to 1900, with possible average mined grades in excess of 20 ounces per tonne silver and lower gold values. One or more gold mineralization events appear to have followed the silver event, or there is mineral zoning with depth. Several ore deposit types are targeted on the Jefferson property:
Six target areas of interest have been identified on the Jefferson property: West Vein (Vein Swarm and Disseminated Ag-Au target); Zone "Pit A" (open pit disseminated/vein Ag-Au); Zone "Pit B" (Open Pit Round Mountain type Au-Ag); Mogul (Vein type Au-Ag); SG-1 / SG-2 (Open Pit Disseminated Round Mountain type Au-Ag); and Porphyry Hill (Vein/Disseminated Ag; Vein-type Au; Open Pit Round Mtn type Au; Room-and-Pillar bulk mineable Skarn Gold; Skarn base metals associated with deep Porphyry; Pluton-centered Carlin-type gold replacements). Mexivada recently completed detailed ground magnetic and CSAMT surveys on the Jefferson property, which were interpreted by Wright Geophysics to indicate a strongly altered core of this large system centered at Porphyry Hill, and a possible strong halo of pyrrhotitic mineralization around the north and northeast perimeter of Porphyry Hill. Parts of this new target area at Porphyry Hill are completely untested for gold and silver by previous drilling. Mexivada is now formulating drill targets, and will then begin permitting for such drilling work with the U.S. Forest Service. Mexivada will attempt to permit its drilling sites on or near to the abundant existing roads and trails present in the project area. We enjoy cordial relations with nearby mine operators Kinross and Barrick and explorer Fronteer Development. Maps & Photos
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