Calculator
Grade and unit conversion
Convert between the units companies use for grade, which are not consistent between commodities or between jurisdictions.
The formula
1 g/t = 1 ppm. 1% = 10,000 ppm. 1 troy ounce per short ton = 34.2857 g/t. 1 kg/t = 1,000 g/t.
What it assumes
- A short ton is 2,000 pounds. Companies reporting in ounces per ton almost always mean the short ton.
- Parts per million is by mass, which is the convention for rock.
Where it stops being reliable
- Converting a unit does not make two grades comparable. A grade only means something against the deposit type and the cut-off it was reported at.
- Some announcements report ounces per tonne rather than per short ton. If the source is unclear, check before converting.