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Wildcat Mining Corporation <br />• SUMMARY <br />Page 1 <br />The May Day and Idaho gold - silver mines are located on the south slope of the <br />La Plata Mountains, at an elevation of about 9,000 feet, in La Plata County, <br />Colorado. Discovered in 1902 -1903, these two mines were the most prolific <br />producers in the district and shipped some of the highest grade ore in Colorado. <br />Mining continued almost continuously during the first decades of the 20 century, <br />until suspended by manpower needs of the war in 1942. Reported past <br />production has been 123,000 ounces gold and 1,142,000 ounces silver; true <br />production is believed to have been substantially greater. Only limited efforts <br />have been made since the 1940's to restart May Day -Idaho production; the <br />mines have been idle for the past two decades of high gold prices. <br />The La Plata Mountains are considered a classic laccolithic mountain range. <br />Sedimentary rock units were uplifted into a broad dome by the intrusion of sills, <br />dikes, and stocks of igneous rocks. Gold and silver deposits throughout the La <br />Plata Mountains were formed during this regional event of igneous intrusion, <br />uplift, faulting, and hydrothermal mineralization. <br />The Idaho and May Day mines both produced ore from a cluster of high -grade <br />gold - silver deposits situated along the major May Day -Idaho fault system. Three <br />styles of mineralization are distinguished: high -grade gold - silver - telluride veins; <br />gold - silver replacement deposits developed at the intersection of mineralized <br />veins with a favorable limestone unit; and fracture - controlled disseminated <br />mineralization within a porphyry dike. The greatest amount of ore was produced <br />from the veins; the highest grade ore was produced from the replacement <br />deposits; the disseminated mineralization was discovered but has been little <br />explored to date. Historically, ore grades have reached several ounces of gold <br />per ton and 10's to 100's of ounces of silver per ton. <br />Host rocks in the May Day mine include sedimentary rock units of Mesozoic age, <br />most importantly the Entrada sandstone, Wanakah formation (including the <br />important Pony Express limestone member), and the Junction Creek sandstone. <br />The sandstone units acted as brittle host rocks favorable for the formation of <br />open vein structures. The Pony Express limestone was locally replaced by pre- <br />forming solutions to create high grade replacement ore. Gold mineralization <br />within the main ore shoot of the May Day vein extended 450 feet vertically; <br />mineralization within the total May Day -Idaho system has been defined over a <br />vertical interval of 1250 feet and laterally for 3000 feet with no evidence for <br />decreasing grade to depth or along strike. <br />Precious metal mineralization within ore veins of the May Day and Idaho mines is <br />discontinuously concentrated in distinct ore shoots. Veins pinch and swell both <br />along strike and dip; the greater portion of most veins is barren. The physical <br />geometry of these ore shoots makes them best mined by highly selective, small - <br />January 2007 May Day — Idaho Mine Colorado <br />