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Introduction 1 Experimental Procedures Source of Materials Preparation and Analysis of the Sample Results and Discussion II Acknowledgments References in THE SEARCH FOR AN ELUSIVE 4.4-MeV a EMITTER IN URANIUM MINERALS ABSTRACTWe describe our search for an unidentified 4.4-MeV a-emitter in Belgian Congo pitchblende and uranium raffinates, and we give a history of observations of 4.4-MeV ac tivity over the last 55 years in radiogenic haloes, zinc ores, monazite, thorite, huttonite, ultrabasic and other abyssal rocks, osiniridium, uranium ores, and raffinates of uranium. We show no evidence of excess 4.4-MeV activity in any of the chemically separated fractions in vestigated. We give upper limits for 4.4-MeV a activity in each of four studied samples.