Gemmological

Gemmology is the science dealing with gemstones, including their identification, properties, classification, evaluation, and origin. It combines mineralogical knowledge with practical techniques used in the jewelry trade to determine authenticity, quality, and potential treatments. Gemmology encompasses natural gemstones, synthetic and lab-grown varieties, simulants, and imitations.

Gemmologists study a gemstone's physical and optical properties, such as refractive index, birefringence, dispersion, pleochroism, and spectrum. They examine inclusions, cut, color, and durability, and use instruments including a loupe, microscope, refractometer, polariscope, spectroscope, and UV–visible spectrophotometer, as well as specific gravity measurements and X-ray analysis where appropriate.

Identification and grading address authenticity and compliance with disclosure standards. Treatments and enhancements (for example heating, diffusion, irradiation, fracture filling, or surface coatings) can affect value and require disclosure. Natural, treated, synthetic, and simulant stones must be distinguished; lab-grown gems differ from natural stones in origin and often in price and risk factors. Some gem families have specific grading criteria in addition to general quality factors.

Industry practice is supported by professional organizations such as laboratories and associations that issue reports on origin, treatments, and identity. Common standards address trade integrity, consumer protection, and ethical sourcing, including processes for conflict-free diamonds in certain jurisdictions. Gemmology education and certification prepare professionals for appraisal, authentication, and consultation in retail, auction, and museum contexts.