African Mining September 2019 | Page 23

MINE EXCURSION  radar survey enabled us to map and deliniate the resource at a low cost. The recovered core has been confirmed as suitable for a high grade roadstone, and allowed us to optimise the design of the crushing circuits that will deliver the scope of material the market demands,” says Ross. The information gleaned from the drilling programme on AST’s concession has been augmented by the GPR surveys which clearly show the depths of the sandstone/quartzite contact. “Loza delivers high resolution imaging of the earths sub-surface to depths of over 200m. A survey using Loza radar allows for fast, accurate and non- invasive geophysical-based surface exploration, and delivers instant and clear images of the subsurface,” says Ross. Oliver Blackmore, one of the three directors at AST, in front of the AquaCycle A200, part of AST’s washplant. Blackmore. He adds that a spacing of 1.2m would be used in the next blast, which will create a finer, more uniform material. AST’s managing director, Ian Ross, says that a crushing circuit will be installed in late 2019, once the mine accesses the quartzite. Radar makes drilling easier “We have been able to drill the quartzite resource very efficiently and with a high degree of accuracy by using a new GPR technology. The www. africanmining.co.za African Mining Publication uw When AST arrived on site four years ago, they started an extensive programme of drilling a resource. For this purpose the company used a high- resolution, low-frequency Loza ground-penetrating radar (GPR) survey. The Chieftain CH2100 X power screen consists of a 13mm top screen, a 10mm middle screen and 8mm bottom screen. African Mining African Mining  September 2019  21