In Stock Gemmology Diamond and moissanite checker A-source Presidium Presidium 02251 €237.00 Highly sensitive and resistant tip design. It uses thermal conductivity tests to determine if a stone is a diamond. Factory calibrated, no need to adjust calibration. Pocket size, easy to carry with you. This model of diamond tester is ideal for gemstone appraisers, gemologists, jewelers, and appraisers of jewelry or pieces of jewelry. Add to cart