The price of assay machines is primarily driven by detection precision (LOD/LOQ), throughput capacity, and the technology used (e.g., XRF, ICP-MS, or ELISA). For industrial gold assaying, X-ray Fluorescence (XRF) machines are cost-effective for non-destructive testing, while Atomic Absorption Spectroscopy (AAS) offers higher precision for trace analysis at a higher price point. Ensure the machine supports automated calibration and has a high-resolution detector (like an SDD detector) to justify the investment.