Official MCP RegistryListed
Digital Gemology: gem identification and gemstone properties
Identify gemstones by refractive index, birefringence, SG, pleochroism and spectrum. Compare 7 gems
First seen 1 Nov 2026. Evidence as of 7 Nov 2026.
4
Tools
From an anonymous probe
1
Source listings
Each with its own history
8
Recorded changes
Since first seen
Tools
| Tool | Description | Behaviour |
|---|---|---|
| absorption_spectrum | What a hand spectroscope shows for one gemstone: each absorption line and band with its position in nanometres, its cause (for example Cr3+ in ruby) and what it looks like, from Digital Gemology's Spectroscope or, for the stones it does not model, published references. | Read-only |
| compare_gemstones | Two gemstones side by side, and the tests that tell them apart: refractive index, birefringence (doubling of back facets, polariscope), specific gravity, dispersion (fire), hardness, pleochroism and spectrum, each with the free tool that shows it. For questions like 'how do I tell diamond from moissanite?'. | Read-only |
| gem_properties | Everything Digital Gemology has on one gemstone: refractive index (both rays for doubly refractive stones), birefringence, dispersion, specific gravity, hardness, crystal system, critical angle, what a refractometer, polariscope and dichroscope show, its pleochroic colors and the lines and bands a hand spectroscope shows, with links to the free tools. For the seven stones our tools model the values are the tools' own; for the others they are published reference values, with their sources. | Read-only |
| identify_gem | Match a stone's test readings against the 36 gemstones in Digital Gemology's data and rank them, saying which reading fits and which does not. Give any of: refractive index, birefringence, specific gravity, optic character, pleochroism, a spectrum line, or that the refractometer read over the limit. A match is a lead, not an identification. | Read-only |
Change history
- identify_gem: description changed (+"36" +"in" +"Gemology's data")
- gem_properties: input schema changed
- gem_properties: description changed (+"has on" +"For the seven stones our tools model the values are the tools' own; for the others they are published reference values, with their sources." -"measures about")
- compare_gemstones: input schema changed
- absorption_spectrum: input schema changed
- absorption_spectrum: description changed (+"Spectroscope or, for the stones it does not model, published references." -"Spectroscope.")
- server instructions changed (+"36 gemstones. Seven come" +"Polariscope: diamond, moissanite, cubic zirconia, ruby, sapphire, emerald and amethyst. 29 more have published reference values with their sources (data 'reference'): colored stones such as aquamarine, tanzanite, spinel and the garnets, and diamond simulants such as YAG, GGG and strontium titanate." +"all of them,")
- Listed (registry)
| Source | Listing | First seen | Last seen | Versions |
|---|---|---|---|---|
| Official MCP Registry | com.digitalgemology/gem-identification | 1 Nov 2026 | 7 Nov 2026 | 1 |