Glossary Term
By Dr. Rashid Karimov Gemological Spectroscopy Editor
Ultraviolet-visible-near-infrared absorption spectroscopy. The standard laboratory technique for quantifying which wavelengths a gemstone absorbs and which it transmits. Color-change diaspore shows characteristic Fe³⁺ absorption near 425 nm and a broad Cr³⁺-related band centered near 580 nm. The absorption profile is a primary diagnostic tool used by GIA and IGS reports.
We use cookies to enhance your experience. Choose which categories of cookies you allow. You can change your preferences at any time.
Required for the website to function. Cannot be disabled.
Enable personalization features like language preferences and accessibility settings.
Help us understand how visitors use our website to improve the user experience.
Used for targeted advertising and tracking across websites.