METHOD OF PREPARING STANDARD COPPER OXIDE SAMPLES FOR SPECTRAL ANALYSIS FOR PRECIOUS METAL CONTENTS Russian patent published in 2000 - IPC

FIELD: analytical methods. SUBSTANCE: to introduce precious metals into copper nitrate solution, first powders of refined iridium, rhodium, and ruthenium and then gold and silver in the form of nitric acid solutions are added. Palladium and osmium in the form of palladium black and refined powder are further rubbed into crushed calcination residue. EFFECT: accelerated preparation of sample, decreased labor-intensiveness when preparing great amounts of materials, and performed certification of metrological characteristics regarding preparation procedure. 3 tbl