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Wildcat Mining Corporation Page 15 <br />geology of the various levels of both the May Day and Idaho mines with the <br />objective of defining exploration targets and ore reserves. Unfortunately, only his <br />text and not his maps remain today. His presentation emphasizes the <br />importance of stratigraphy as an ore control and the critical importance of careful <br />geological mapping and structural interpretation for ore discovery. He described <br />ore occurrences as being of extremely high grade (up to 3000 opt Ag and 4 -7 opt <br />Au) but characteristically thin and structurally disrupted. Mr. Garrey <br />recommended installation of a mill on the property to permit economic production <br />of lower grade ores. <br />The archives contain an anonymous report — again missing maps - dated July <br />1929 and possibly authored by Mr. H. Mills. This report describes a number of <br />potential exploration targets defined by geology, stratigraphy, and structure. Ore <br />dressing at the time is described as consisting of screening to separate fines, <br />washing, and delivering the oversize to a picking belt for hand sorting. Picked <br />ore was shipped to the AS & R smelter in Durango. An assay sheet attached to <br />the report reports 27 samples with gold grades between trace and 1.55 opt, <br />averaging 0.35 opt Au, and silver grades between 0.5 and 31.8 opt, averaging <br />6.0 opt Ag. <br />Michael Fominyah submitted a "Report on Estimates of the Reserves of the <br />Idaho and May Day Veins of the Idaho Mine" to La Plata Mountains Gold Mines <br />Inc. dated October 1936. The average gold grades of the proved ore blocks <br />• varied from 0.20 -0.35 opt Au and 2.4 -10.4 opt Ag, which Mr. Fominyah qualifies <br />as conservative estimates. He described the veins as being strong, well- defined <br />and consistent, pinching and swelling from fractions of an inch to as much as 10- <br />12 feet in thickness. It is probable that most of the reserves defined in this paper <br />have been extracted, but this assumption warrants review. <br />Ross B. McCausland completed a report on the May Day mine dated April 1941. <br />The report contains a useful summary of the mine history, geology, and <br />metallurgy. As with earlier reports, McCausland outlined a number of exploration <br />targets. Among the more speculative and interesting observations is that veins <br />elsewhere in the La Plata Mountains make good ore in formations below the tight <br />shales of the Dolores formation. He recommended exploration of the known <br />veins within the Cutler and deeper formations. Shortly after submission of this <br />report, the mine was closed for the war. <br />The definitive document for the geology and ore deposits of the La Plata District <br />is United States Geological Survey Bulletin 219 by Edwin B. Eckel published in <br />1949. This report, the result of a three -year professional investigation, is a <br />comprehensive presentation of the district geology and mineral deposits, with <br />excellent discussions of all the known mines and deposits. The maps of Eckel <br />remain the most complete geologic maps of the May Day and Idaho Mines. <br />• <br />January 2007 <br />May Day — Idaho Mine Colorado <br />