OREAS 257b
Description
Description
OREAS 257b was prepared from gold-bearing Wilber Lode oxide ore from the Andy Well Gold Project. The Wilber Lode is a shear- hosted, narrow vein, quartz lode-style gold deposit situated within the Meekatharra-Wydgee greenstone belt in the Archaean Yilgarn Craton of Western Australia. The common primary mineral assemblage as stated by Mason and Harris (2011, 2012, cited in Hingston et al, 2014) is quartz, calcite, chlorite, fuchsite, pyrite, galena, sphalerite, chalcopyrite and gold. The host rock consists of a complex sequence of weathered Archaean meta-basalt and meta-porphyritic rocks derived from a primary mineralogy of albite, actinolite, chlorite, sericite, biotite, calcite, zoisite, muscovite, quartz and titanate. The Andy Well deposit is located approximately 45km north of Meekatharra in the Murchison region of Western Australia.
Thirty-five commercial analytical laboratories participated in the program to certify:
- Gold by fire assay;
- Full ICP-OES and ICP-MS elemental suites by 4-acid digestion;
- Gold by 15-50g aqua regia digestion;
- Gold by cyanide leach.
|
Analyte
|
Certified Value
|
1SD
|
95% Confidence Limits Low
|
95% Confidence Limits High
|
Method
|
|---|---|---|---|---|---|
| Au, Gold (ppm) | 14.22 | 0.373 | 14.09 | 14.34 | Pb Fire Assay |
| Au, Gold (ppm) | 14.17 | 0.447 | 13.97 | 14.37 | Aqua Regia Digestion (sample weights 10-50g) |
| Au, Gold (ppm) | 13.96 | 0.460 | 13.71 | 14.20 | Cyanide Leach |
| Ag, Silver (ppm) | 2.36 | 0.189 | 2.27 | 2.44 | 4-Acid Digestion |
| Al, Aluminium (wt.%) | 5.14 | 0.180 | 5.07 | 5.22 | 4-Acid Digestion |
| As, Arsenic (ppm) | 65 | 3.9 | 64 | 67 | 4-Acid Digestion |
| Ba, Barium (ppm) | 293 | 11 | 289 | 297 | 4-Acid Digestion |
| Be, Beryllium (ppm) | 0.61 | 0.07 | 0.58 | 0.64 | 4-Acid Digestion |
| Bi, Bismuth (ppm) | 0.88 | 0.038 | 0.87 | 0.90 | 4-Acid Digestion |
| Ca, Calcium (wt.%) | 0.579 | 0.024 | 0.570 | 0.589 | 4-Acid Digestion |
| Cd, Cadmium (ppm) | 0.084 | 0.015 | 0.077 | 0.090 | 4-Acid Digestion |
| Ce, Cerium (ppm) | 13.7 | 0.83 | 13.3 | 14.1 | 4-Acid Digestion |
| Co, Cobalt (ppm) | 26.2 | 1.52 | 25.5 | 26.8 | 4-Acid Digestion |
| Cr, Chromium (ppm) | 302 | 51 | 280 | 324 | 4-Acid Digestion |
| Cs, Caesium (ppm) | 0.62 | 0.034 | 0.61 | 0.63 | 4-Acid Digestion |
| Cu, Copper (ppm) | 148 | 7 | 145 | 151 | 4-Acid Digestion |
| Dy, Dysprosium (ppm) | 1.34 | 0.064 | 1.31 | 1.38 | 4-Acid Digestion |
| Er, Erbium (ppm) | 0.84 | 0.056 | 0.81 | 0.87 | 4-Acid Digestion |
| Eu, Europium (ppm) | 0.38 | 0.020 | 0.36 | 0.40 | 4-Acid Digestion |
| Fe, Iron (wt.%) | 3.16 | 0.124 | 3.11 | 3.21 | 4-Acid Digestion |
| Ga, Gallium (ppm) | 11.9 | 0.74 | 11.6 | 12.3 | 4-Acid Digestion |
| Gd, Gadolinium (ppm) | 1.32 | 0.083 | 1.27 | 1.37 | 4-Acid Digestion |
| Hf, Hafnium (ppm) | 1.24 | 0.067 | 1.22 | 1.26 | 4-Acid Digestion |
| Ho, Holmium (ppm) | 0.29 | 0.014 | 0.28 | 0.30 | 4-Acid Digestion |
| In, Indium (ppm) | 0.030 | 0.006 | 0.028 | 0.031 | 4-Acid Digestion |
| K, Potassium (wt.%) | 1.15 | 0.042 | 1.13 | 1.16 | 4-Acid Digestion |
| La, Lanthanum (ppm) | 7.19 | 0.384 | 7.01 | 7.38 | 4-Acid Digestion |
| Li, Lithium (ppm) | 23.4 | 1.34 | 22.9 | 23.9 | 4-Acid Digestion |
| Lu, Lutetium (ppm) | 0.11 | 0.01 | 0.11 | 0.12 | 4-Acid Digestion |
| Mg, Magnesium (wt.%) | 2.13 | 0.087 | 2.10 | 2.17 | 4-Acid Digestion |
| Mn, Manganese (wt.%) | 0.034 | 0.001 | 0.034 | 0.035 | 4-Acid Digestion |
| Mo, Molybdenum (ppm) | 9.96 | 0.530 | 9.74 | 10.18 | 4-Acid Digestion |
| Na, Sodium (wt.%) | 0.231 | 0.012 | 0.225 | 0.237 | 4-Acid Digestion |
| Nb, Niobium (ppm) | 1.58 | 0.107 | 1.53 | 1.62 | 4-Acid Digestion |
| Nd, Neodymium (ppm) | 5.78 | 0.229 | 5.67 | 5.89 | 4-Acid Digestion |
| Ni, Nickel (ppm) | 123 | 6 | 120 | 125 | 4-Acid Digestion |
| P, Phosphorus (wt.%) | 0.015 | 0.001 | 0.015 | 0.016 | 4-Acid Digestion |
| Pb, Lead (ppm) | 15.8 | 1.8 | 14.9 | 16.7 | 4-Acid Digestion |
| Pr, Praseodymium (ppm) | 1.56 | 0.066 | 1.52 | 1.59 | 4-Acid Digestion |
| Rb, Rubidium (ppm) | 44.9 | 2.32 | 44.0 | 45.9 | 4-Acid Digestion |
| S, Sulphur (wt.%) | 0.111 | 0.006 | 0.108 | 0.113 | 4-Acid Digestion |
| Sc, Scandium (ppm) | 19.2 | 1.44 | 18.6 | 19.8 | 4-Acid Digestion |
| Sm, Samarium (ppm) | 1.21 | 0.093 | 1.17 | 1.26 | 4-Acid Digestion |
| Sn, Tin (ppm) | 0.50 | 0.041 | 0.48 | 0.51 | 4-Acid Digestion |
| Sr, Strontium (ppm) | 32.0 | 1.86 | 31.2 | 32.8 | 4-Acid Digestion |
| Ta, Tantalum (ppm) | 0.10 | 0.008 | 0.10 | 0.11 | 4-Acid Digestion |
| Tb, Terbium (ppm) | 0.21 | 0.02 | 0.20 | 0.22 | 4-Acid Digestion |
| Te, Tellurium (ppm) | 0.41 | 0.06 | 0.39 | 0.44 | 4-Acid Digestion |
| Th, Thorium (ppm) | 1.85 | 0.126 | 1.79 | 1.90 | 4-Acid Digestion |
| Ti, Titanium (wt.%) | 0.198 | 0.009 | 0.194 | 0.201 | 4-Acid Digestion |
| Tl, Thallium (ppm) | 0.35 | 0.019 | 0.34 | 0.36 | 4-Acid Digestion |
| Tm, Thulium (ppm) | 0.11 | 0.01 | 0.10 | 0.12 | 4-Acid Digestion |
| U, Uranium (ppm) | 0.52 | 0.036 | 0.51 | 0.53 | 4-Acid Digestion |
| V, Vanadium (ppm) | 139 | 6 | 136 | 141 | 4-Acid Digestion |
| W, Tungsten (ppm) | 15.3 | 1.17 | 14.8 | 15.8 | 4-Acid Digestion |
| Y, Yttrium (ppm) | 7.38 | 0.262 | 7.28 | 7.47 | 4-Acid Digestion |
| Yb, Ytterbium (ppm) | 0.80 | 0.048 | 0.77 | 0.82 | 4-Acid Digestion |
| Zn, Zinc (ppm) | 57 | 3.6 | 56 | 59 | 4-Acid Digestion |
| Zr, Zirconium (ppm) | 45.5 | 2.36 | 44.6 | 46.4 | 4-Acid Digestion |
