OREAS 281

OREAS 281 was prepared using a combination of gold-bearing materials from the Leeville and Deep Post deposits located along the Carlin Trend in Nevada, as well as synthetic oxide diluents emulating the mineralogical and geochemical signature of siliceous and carbonate-rich Carlin-style deposits.

The mineralisation in these deposits is typified by finely disseminated gold hosted in siliceous, carbonaceous, and sulphidic sedimentary rocks, characteristic of low-grade, oxide Carlin-style systems.

OREAS 281 has been characterized for gold, majors and traces using the following methods:

• Gold by fire assay with AAS, ICP-OES or ICP-MS finish
• Full ICP-OES and ICP-MS elemental suites by 4-acid (HNO3-HF-HClO4-HCl) digestion
• Full ICP-OES and ICP-MS elemental suites by aqua regia digestion
• Total Carbon and Sulphur with infrared combustion analysis

Certified values for applicable analytes are operationally defined for each method, with results under OREAS ISO 17034 scope of accreditation.