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| | |  43-101 Report Mexivada's Jefferson property comprises a contiguous block of 46 unpatented lode mining claims, totaling approximately 910 acres, that are either 100% owned by Mexivada or under option to the company by a private owner. There are five small patented claims located inside the Jefferson property that are controlled by a private land owner and by Round Mountain Gold Company ("RMGC", Barrick-Kinross JV). 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 +15,000,000 ounce Round Mountain Mine and the nearby +1,000,000 ounce Gold Hill gold mine, both owned or controlled by RMGC, and Newmont's +3,000,000 ounce Northumberland Mine, a Carlin-type, open pitted former gold producing mine. The Jefferson Canyon mining district, one of Nevada's first mining camps, 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 starting in 2005, 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 underground mines were operating along the northwest-trending Prussian vein system, producing over ten thousand tons of high-grade gold-silver ores, yielding approximately between 400,000 to 800,000 ounces of silver and some gold, from workings on high-grade veins. 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 at the nearby Round Mountain and Gold Hill mines and at Ziggurat. 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 Echo Bay-Copper Range drilling. The volcanic tuffs were deposited in the depressions created when the several calderas in the regional Mt. Jefferson area formed, which includes the Ziggurat area. 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, and is thought to be a major, crustal bounding block fault and regional control on gold-silver mineralization. Jefferson Canyon is a major, west-northwest trending continental structural boundary that was re-activated many times by faulting, providing repeated open spaces that were later host to episodes of gold-silver mineralization. Cretaceous mesozonal "tombstone" granites form the old, 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 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 copper-bearing base metal skarn and porphyry mineralization, as may also occur to the northeast of Ziggurat at the Northumberland Mine. Correlations with historic mine workings suggest that the non-skarn alteration is related to younger 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 series of north-northwest trending Carlin-age hypabyssal igneous dikes then were intruded in the area, as mapped by Dan Shawe of the USGS. Carlin-style gold mineralization also was imprinted on the rocks in the area in Oligocene time (36-38 Ma?), such as occurs at Northumberland and at the Steigmeyer showing south of the Round Mountain Mine. A major silver-(gold) 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 a late, yet-unexplained silver-to-gold mineral zoning present, as high gold values to 0.85 oz/ton gold are present in the "Pit B" area at Jefferson, along with high silver values to in excess of 40 oz./ton silver. Several ore deposit types are being targeted on the Jefferson property by Mexivada:
Mexivada has completed airborne- and detailed ground magnetic, gravity, 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 at Jefferson and is compiling data for an updated, 43-101 non-compliant gold-silver 3-D Mining Resource Estimate, using industry-standard Vulcan 3-D modeling software. A previous property owner wrote a Mineable Resource Estimate for part of the property, based on certain previous drilling. This resource estimate will allow Mexivada to better formulate a detailed Phase 2 drilling program in an attempt to block out gold-silver ore reserves and find new blocks of ore-bearing rocks. Mexivada then will 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. Mexivada enjoys cordial relations with nearby mine operators Kinross and Barrick and Newmont. Maps & Photos
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