Comparative Study: Gravimetric Finish vs AAS Finish in High-Grade Gold Assaying

Analytical Detection Limits & Finish Selection

In commercial geochemical assaying, choosing between Atomic Absorption Spectrometry (AAS) and micro-balance gravimetric finish depends on grade distribution. While AAS provides ultra-sensitive sub-ppm quantification (0.01 to 10 g/t Au), high-grade intercepts require gravimetric verification to prevent dilution multiplier inaccuracies.

Inquarting & Parting Protocols

Accurate gravimetric parting requires adding high-purity silver wire at a 3:1 silver-to-gold ratio prior to fusion. Following cupellation at 920°C, the silver is parted using dilute and concentrated nitric acid cycles, and the annealed gold cornet is weighed on an ultra-microbalance sensitive to 0.0001 mg.

Defensibility in Resource Estimation

Our dual-finish protocol automatically triggers gravimetric repeats for any sample surpassing 10 ppm Au, providing certified duplicate certainty for NI 43-101 and JORC-compliant resource reporting.