Abstract
A qualitative test program to study placer gold nugget recovery using an eddy-current separator was sponsored jointly by the University of Alaska and Eriez Magnetics. Various gold nuggets from Alaska, ranging in size from 6.4 to 63.5 mm, were tested. All tests were performed using an Eriez Laboratory ESC, Model REA, fitted with a 2,000-gauss, surface field-strength magnetic rotor. The belt speed was set to 91 ml min (300fpm) and the rotor speed was set to 2,500 rpm in the forward direction. The splitter was adjusted to just reject the largest pieces of rock, which averaged 76 × 102 × 127 mm. Based on the results of this limited test work, it is being recommended to placer gold mine operators that ECS technology is a viable and practical concentration technology for coarse gold recovery. Silver and platinum were also tested.
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Preprint number 03-041, presented at the SME Annual Meeting, Feb. 24–26, 2003, Cincinnati, Ohio. Discussion of this peer-reviewed and approved paper is invited and must be submitted to SME Publications Dept. prior to May 31,2005.
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Walsh, D.E., Wernham, J.A. & Norrgran, D.A. Eddy-current separator technology as a novel approach to Alaskan placer gold recovery. Mining, Metallurgy & Exploration 21, 189–192 (2004). https://doi.org/10.1007/BF03403183
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DOI: https://doi.org/10.1007/BF03403183