Wed, 06 May 2026 09:49:19 +0000

What Every Gemstone Hands Over the Diamond Tester Won’t Let You See When it comes to gemstone evaluation, the diamond tester is one of the most trusted tools—a high-tech instrument designed to distinguish real diamonds from synthetics and common imitations. But behind its sleek surface lies a hidden truth: there are aspects of every gemstone that even the most advanced diamond tester cannot reveal. While these devices excel at detecting synthetics and common substitutes, they often remain silent on deeper secrets hidden within the stone. ### The Limitations of Diamond Testers—What They Don’t Show At its core, a diamond tester—whether thermal, electrical, or optical—relies on measurable properties like thermal conductivity, refractive index, or electrical resistance. These tests help confirm a stone’s identity and detect common man-made stones such as CVD or flux-grown diamonds. However, they cannot uncover subtle features invisible to physics-based diagnostics, including: