#### Mineral Sampling ScienceDirect

· A gold ore was crushed in a jaw crusher down to 3 mm and to 1 mm in a cone crusher and finally in a rod mill to minus 75 μm and sampled at each stage The standard deviation at the first stage was ±10 ppm ±1 ppm at the second stage and ± at the third stage The confidence level in assaying was ± % Estimate the minimum mass of sample to be taken at each stage