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Applied Mineral Inventory Estimation presents a comprehensive applied approach to the estimation of mineral resources/reserves with particular emphasis on the geological basis of such estimations, the need for and maintenance of a high quality assay data base, the practical use of a comprehensive exploratory data evaluation, and the importance of a comprehensive geostatistical approach to the estimation methodology. Practical problems and real data are used throughout as illustrations: each chapter ends with a summary of practical concerns, a number of practical exercises and a short list of references for supplementary study. This textbook is suitable for any university or mining school that offers senior undergraduate and graduate student courses on mineral resource/reserve estimation. It will also be valuable for professional mining engineers, geological engineers and geologists working with mineral exploration and mining companies.

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Galena lead isotope data from Ainsworth-Bluebell, Slocan, and Moyle camps in southeastern British Columbia can be interpreted in terms of mixing of lead from two different sources, both of which follow simple growth-curve lead evolution. The more radiogenic source can be approximated using the three-stage shale curve of Godwin and Sinclair (1982) which is thought to represent evolution of lead in the upper crustal, continentally derived sedimentary rocks which host these deposits. The two-stage Bluebell growth curve through the Bluebell datum provides an estimate of the uranium-poor lead source which may be the lower crust, the upper mantle, or a mixture of both. The Bluebell curve departs from Stacey and Kramers' (1975) average growth curve at 3.77 b.y., with a •t value of 9.23.Mixing line isochrons drawn between these two curves at ages corresponding to the best estimates for the mineralization ages at these three mining camps closely fit the lead isotope data. This supports the age estimates for all three camps and, in particular, substantiates a Lower Cambrian age for the original mineralization in the Ainsworth and Bluebell deposits. Mixing is assumed to take place at the time of mineralization and may be attributed to magmatic activity in the Moyie and Slocan camps. Additional data from deposits in the Purcell anticlinorium in Idaho and Montana (Zartman and Stacey, 1971), the Carmi and Tillicum Mountain gold-silver camps in south-central BritishColumbia, and the Galena Hill silver veins in the Yukon Territory demonstrate the applicability of this model to a large part of the Omineca belt and show how it may be used to date both epigenetic and syngenetic or penecontemporaneous deposits of unknown age.