Presidium has been developing professional gemstone testing instruments for decades and is trusted by jewellers, goldsmiths, gemologists and appraisers worldwide. Designed for accuracy, reliability and ease of use, Presidium gemstone testers help professionals identify a wide range of coloured gemstones quickly and confidently.

Reliable gemstone identification is essential for accurate valuation, purchasing decisions and customer confidence. Modern testing instruments assist in distinguishing natural gemstones from synthetic stones and simulants, providing valuable information for professional gemstone analysis.

Whether you are looking for the proven Gem Tester II (PGT II), the Gem Indicator for fast thermal conductivity testing, the versatile Duo Tester (PDT II) or the professional Refractive Index Meter II, Presidium offers the right solution for every application. The product range is complemented by specialist instruments such as the Synthetic Ruby Identifier (SRI), designed to identify synthetic rubies quickly and reliably.