We have seen several articles today stating Platinum Group Metals (PGMs) in ppb. Ppb stands for parts per billion and ppm stands for parts per million. Labs conduct their analysis/assays of the samples with machines that are set to report results as ppb or ppm depending on the concentrations involved. The results are them reported as g/t, % or oz/t depending on the preference of the company that is paying for the assays.
As a quick reference 1000 ppb equals 1 g/t and 10,000 ppm equals 1%. So when you see 700 to 900 ppb they are indicating assays of 0.7 to 0.9 g/t.
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