Elwin L. Mosier Henry V. Alminas 1976 In many instances total-rock and sieved-soil and stream-sediment samples lack the sensitivity and contrast required for reconnaissance exploration and necessary in the search for blind ore deposits. Heavy-mineral concentrates incorporate the required sensitivity and contrast but are overly expensive for two reasons: time-consuming sample preparation is required to obtain them, and they cannot be easily derived from all bulk-sample types. Trace-metal-content comparisons of the oxalic-acid-leachable portions with heavy-mineral concentrates show that the leachates are equal to the heavy-mineral concentrates in sensitivity and contrast. Simplicity of preparation and the resultant cost savings are additional advantages of this proposed method. application/pdf 10.3133/ofr76275 en U.S. Geological Survey, Oxalic-acid leaching of rock, soil, and stream-sediment samples as an anomaly-accentuated technique reports