Determine the gross gold weight used
Determine the net finished gold weight recovered
Subtract net finished weight from gross weight to get wastage weight
Use the formula: Gold Wastage = Gross Gold Weight – Net Gold Weight
Calculate wastage percentage using: (Gold Wastage ÷ Gross Gold Weight) × 100
If purity changes matter, convert all weights to pure gold equivalent before calculating
For karat-based gold, convert to pure gold using: Pure Gold Weight = Total Weight × (Karat ÷ 24)
Compare actual wastage against expected wastage for the process
Include losses from melting, polishing, filing, dust, and scrap if applicable
Record all weights in the same unit before calculation