Comparison of hot hydroxylamine hydrochloride and oxalic acid leaching of stream sediment and coated rock samples as anomaly enhancement techniques

L.H. Filipek; T. T. Chao; P. K. Theobald

doi:10.1016/0375-6742(82)90018-8

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Comparison of hot hydroxylamine hydrochloride and oxalic acid leaching of stream sediment and coated rock samples as anomaly enhancement techniques

L.H. Filipek·T. T. Chao·P. K. Theobald

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Abstract

A hot hydroxylamine hydrochloride (H-Hxl) extraction in 25% acetic acid is compared with the commonly used oxalic acid extraction as a method of anomaly enhancement for Cu and Zn in samples from two very different metal deposits and climatic environments. Results obtained on minus-80-mesh stream sediments from an area near the Magruder massive sulfide deposit in Lincoln County, Georgia, where the climate is humid subtropical, indicate that H-Hxl enhances the anomaly for Cu by a factor of 2 and for Zn by a factor of 1.5, compared to the oxalic method. Analyses of Fe oxide-coated rock samples from outcrops overlying the North Silver Bell porphyry copper deposit near Tucson, Arizona, where the climate is semi-arid to arid, indicate that both techniques effectively outline the zones of hydrothermal alteration. The H-Hxl extraction can also perform well in high-carbonate or high-clay environments, where other workers have suggested that oxalic acid is not very effective. Therefore, the H-Hxl method is recommended for general exploration use.

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L.H. Filipek, T. T. Chao, P. K. Theobald. 1982. Comparison of hot hydroxylamine hydrochloride and oxalic acid leaching of stream sediment and coated rock samples as anomaly enhancement techniques. https://doi.org/10.1016/0375-6742(82)90018-8

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