The most critical factor is the Gold Grade (Au content), typically measured in grams per ton (g/t). Buyers must distinguish between high-grade (>10 g/t), medium-grade (4-10 g/t), and low-grade (<4 g/t) ores. Additionally, analyze the mineralogical composition (e.g., oxide vs. sulfide ores) as this dictates the recovery rate and the required extraction technology (cyanidation, flotation, or gravity separation). Ensure the moisture content is clearly defined to avoid paying for water weight during shipping.