Every bar weighed, sampled and assayed.
Gold is paid for on its fine gold content, so we measure it carefully at source and verify it again at the refinery.
At source
Quality control in Tanzania
- Weighing
- Each bar is weighed on calibrated scales and recorded on the lot's weight list.
- Sampling
- Samples are taken from each bar for laboratory analysis.
- Assay
- An independent laboratory reports gold and silver content by bar and by lot.
- Sealing
- Bars are packed and sealed, and the seal numbers are written on the shipping documents.
At the refinery
Final assay and settlement
- Arrival
- Seals are checked against the documents and the bars are weighed again on receipt.
- Melt & assay
- The refinery melts the lot into a homogeneous bar and assays it for gold and silver.
- Comparison
- The refinery's result is compared with the source assay.
- Umpire assay
- If the two results differ by more than the limit agreed in the contract, an independent umpire laboratory decides.
- Settlement
- Payment is made on the final fine gold content, as set out in the contract.
Fine gold content is the weight of pure gold in a lot: the gross weight of the bars multiplied by their gold purity. A 10 kg lot at 92% gold contains 9.2 kg of fine gold.
Supply & offtake
Empowering industries with every ounce extracted.