**Automated Quantitative Mineralogy Optimized for Simultaneous Detection of (Precious**/**Critical) Rare Metals and Base Metals in A Production-Focused Environment**

#### **Mathis Warlo 1,\*, Christina Wanhainen 1, Glenn Bark 1, Alan R. Butcher 2, Iris McElroy 3, Dominique Brising 3 and Gavyn K. Rollinson 4**


Received: 17 June 2019; Accepted: 15 July 2019; Published: 18 July 2019

**Abstract:** Automated Scanning Electron Microscopy (ASEM) systems are applied in the mining industry to quantify the mineralogy of the ore feed and products. With society pushing towards sustainable mining, this quantification should be comprehensive and include trace minerals since they are often either deleterious or potential by-products. Systems like QEMSCAN® offer a mode for trace mineral analysis (TMS mode); However, it is unsuitable when all phases require analysis. Here, we investigate the potential of detecting micron-sized trace minerals in fieldscan mode using the QEMSCAN® system with analytical settings in line with the mining industry. For quality comparison, analysis was performed at a mining company and a research institution. This novel approach was done in full collaboration with both parties. Results show that the resolution of trace minerals at or below the scan resolution is difficult and not always reliable due to mixed X-ray signals. However, by modification of the species identification protocol (SIP), quantification is achievable, although verification by SEM-EDS is recommended. As an add-on to routine quantitative analysis focused on major ore minerals, this method can produce quantitative data and information on mineral association for trace minerals of precious and critical metals which may be potential by-products in a mining operation.

**Keywords:** automated scanning electron microscopy; QEMSCAN®; trace minerals; gold
