This toolkit covers every quantitative and qualitative test a practising gemmologist needs for systematic identification. All calculations run client-side in the browser using the same mineral database that powers the mineral reference pages: 96 families including natural species, lab-grown synthetics, simulants, and composite stones. No data is transmitted to any server; readings stay on your device.

The tools are organised across six categories. Measurement & Calculation handles the two primary quantitative tests (specific gravity and refractive index) alongside birefringence, critical angle, carat estimation, and the Hanneman/Hodgkinson over-the-limit shortcut for stones with RI above 1.81. Optical Properties supports the polariscope and dichroscope workflow, with a refractometer simulator, pleochroism reasoner, and optic-sign determination. Lab Equipment covers spectroscope absorption-band reading, an inverse band-matcher for species lookup, and UV fluorescence interpretation. Gem Identification provides a filtered database query to narrow candidates by RI, SG, crystal system, and optical character. Advanced Analysis integrates treatment-detection evidence weighting and GIA cut-grade proportion analysis. Unit Conversions handles metric/troy/decimal-carat and temperature scales used in refractometer corrections.

The workflow mirrors the FGA Diploma practical examination protocol: start with non-destructive observations, then RI, then SG, then spectroscope for ambiguous cases, and apply qualitative confirmatory tests last. Each tool includes a brief methodology note so students building examination technique can understand not just the result but the reasoning behind it.