Specifications
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CRM State:
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Matrix:
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Mineralisation:
OREAS 61e was prepared from coarse reject splits of gold-silver ore samples from the Cracow mine located 500km northwest of Brisbane in Queensland, Australia. Cracow is a low sulphidation epithermal deposit hosted by meta-andesitic volcanics. High grade gold mineralisation occurs within fissure quartz veins and is associated with zones of silicification, present as quartz lode breccia and as quartz vein breccia.
Twenty-six commercial analytical laboratories participated in the program to characterise Au and Ag. The following methods were employed:
Analyte | Certified Value | 1SD | 95% Confidence Limits Low | 95% Confidence Limits High | Method |
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Au, Gold (ppm) | 4.43 | 0.152 | 4.38 | 4.48 | Pb Fire Assay |
Ag, Silver (ppm) | 5.27 | 0.431 | 5.10 | 5.44 | 4-Acid Digestion |
Au, Gold (ppm) | 4.51 | 0.264 | 4.39 | 4.63 | Aqua Regia Digestion |
S, Sulphur (wt.%) | 0.790 | 0.029 | 0.757 | 0.823 | 4-Acid Digestion |
Ag, Silver (ppm) | 5.37 | 0.382 | 5.21 | 5.54 | Aqua Regia Digestion |
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