Video

Why Macraes decommissioned its fire assay lab | Ben Baxter, Geology Superintendent, Macraes Gold Mine

October 2026 · 10 min Presented by Ben Baxter, Geology Superintendent, Macraes Gold Mine

Macraes targeted a 48-hour turnaround time under fire assay. One repeated job would blow it out to 60+ hours with diggers parked up waiting on results. Ben Baxter, Geology Superintendent at OceanaGold’s Macraes mine, explores the problems with fire assay: additive error, blown-out turnaround times, and the costs of having production waiting on assay results, and the changes made on site mine once PhotonAssay™ went live.

Chapters

0:00 Introduction
0:28 The problems with fire assay
2:03 Why PhotonAssay™?
3:07 What did you want to know about PhotonAssay™
4:15 What were the PhotonAssay™ benefits?
4:42 How was the transition from fire assay to PhotonAssay™?
5:35 Installing on site
5:56 Decommissioning the fire assay lab
6:24 What's changed since PhotonAssay™ deployment?
8:09 Rethinking the mine operation
8:57 The impact of reusable CRMs
9:40 What is next for Macraes
10:01 Do you recommend PhotonAssay™?

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