FIELD NOTES / 06
From a mineral to a material
Production is different from exports.
A chemical element is not the same thing as a mineral or an ore. An ore is mined because a useful material can be recovered under the relevant economic and technical conditions.
Mine production, refinery output, reserves and exports measure different things. A country may export material mined elsewhere.
Always read the commodity, year, unit and source together. A tonne of ore is not a tonne of contained metal. An unknown value is not zero.