Matching Carbide Grade to Abrasive Greenstone
Guyana's hinterland gold ground is dominated by abrasive Proterozoic greenstone and silicified shear zones that grind down soft carbide grades long before a bit reaches its footage target. The answer is a tougher, higher-cobalt tungsten-carbide grade: more cobalt binder absorbs impact and resists fracture under percussion, while a controlled grain size keeps the inserts and buttons from chipping in blocky, fractured rock. Getting that balance right is the difference between a bit that finishes a bench and one that comes out of the hole at half gauge.
Because Volga Burmash synthesises its own tungsten carbide products in-house — from WC-Co powder through to pressed inserts and buttons — VBM Guyana can specify the grade to the formation rather than to whatever stock is on the shelf. For mixed and softer sections we pair those carbide grades with sealed-bearing tricone bits; for the hardest quarry granite we move to DTH button bits running the most impact-resistant grades.
Not sure which grade or bit type suits your ground? Our gold mining and quarrying guide walks through formation hardness, flush selection and cost-per-metre for Guyanese conditions, or send us your offset data through the form below for a formation-matched recommendation.