The price of a gold tester is primarily driven by its underlying technology. X-Ray Fluorescence (XRF) Analyzers are the most expensive (ranging from $3,000 to $15,000+) because they provide non-destructive, laboratory-grade elemental analysis of all metals in an alloy. Electronic/Conductivity Testers are mid-range options ($50 - $500) suitable for quick retail checks but may struggle with thick gold plating. Ultrasonic Testers are used specifically to detect tungsten cores inside gold bars. For B2B buyers, investing in XRF technology is recommended for high-volume scrap gold or jewelry trading to ensure 100% accuracy and prevent financial loss.