Ministry of Gems — Gemmology

Verified gemmology reference: 168 FGAA-reviewed terms and 25 handbooks, with citable URLs.

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What it can do

    What data it sees

    Do you need an account

    No: the server works without sign-in

    Verified gemmology reference: 168 FGAA-reviewed terms and 25 handbooks, with citable URLs.

    How to connect

    How to connect Ministry of Gems — Gemmology to Claude

    The server address to paste into Claude settings:

    https://mog-concierge.33guruge.workers.dev/mcp

    1. Open Claude (claude.ai or the desktop app).
    2. Go to Settings → Connectors.
    3. Click Add custom connector.
    4. Paste the server address copied below into Remote MCP server URL and click Add.
    5. In a chat, click + → Connectors and switch the new connector on.

    Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

    Authorization

    After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

    How to connect Ministry of Gems — Gemmology to ChatGPT

    The server address to paste into ChatGPT settings:

    https://mog-concierge.33guruge.workers.dev/mcp

    1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
    2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
    3. Open Settings → Connectors and click Create.
    4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
    5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
    6. In a new chat open + → Apps/Connectors and enable the connector.

    OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

    Authorization

    On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

    How to connect Ministry of Gems — Gemmology to Cursor

    The server address to paste into Cursor settings:

    https://mog-concierge.33guruge.workers.dev/mcp

    Fastest: click Open in Cursor below and confirm the prompt.

    Manually:

    1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
    2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
    3. Save the file. The server appears in the MCP list; authorize it there if asked.

    Authorization

    If the service needs sign-in, an authorize button appears next to the server in the MCP list.

    Server tool list (13)

    Raw names from tools/list. Only developers need these.

    define_gem_termLook up a gemmological term in The Gem Lexicon of Ministry of Gems — 215 definitions verified by an FGAA-qualified gemmologist. Returns the definition, its subject section, and a citable anchor URL. Use for terms such as padparadscha, corundum, parti sapphire, unheated, or asterism.
    search_gem_knowledgeKeyword search across the Ministry of Gems gemmological reference library — 215 lexicon definitions and 25 full-length buyer's handbooks, searched in full text across every section. Returns ranked results, each with the matched passage and a citable URL that deep-links to the chapter.
    list_gem_termsList the gemmological terms available in The Gem Lexicon, optionally filtered to one subject section. Use this to discover what can be defined before calling define_gem_term.
    verify_gem_passportCryptographically verify a Ministry of Gems Digital Gemstone Passport by stone ID. Recomputes the SHA-256 digest of the signed record and checks its Ed25519 (EdDSA) signature against the house public key, then returns the attested record: species, carat, dimensions, cut, colour, clarity, origin, treatment and certificate status. Use when a buyer asks whether a stone or its passport is genuine, or before quoting any fact about a specific Ministry of Gems stone.
    search_gem_inventorySearch the live Ministry of Gems catalogue of natural loose gemstones and finished jewellery — Ceylon and Australian sapphires, rubies, spinels, Australian opals, emeralds and more — with prices in Australian dollars, availability, carat weight and a link to buy. Filter by type (gems, ring, pendant, earrings), carat range and price range. Every loose gem returned carries a verifiable Digital Gemstone Passport.
    sapphire_price_guideWhat natural sapphires actually cost per carat in Australian dollars, from Ministry of Gems' published price guide: bands by origin (Australian, Ceylon) and size, with the stone count behind each band and the date the bands were computed. Answers "how much is a 2 carat sapphire" honestly, as a house guide rather than a market index.
    gem_propertiesMohs hardness, refractive index, specific gravity, birefringence and crystal system for a gem species (diamond, corundum/sapphire/ruby, emerald, spinel, opal, tourmaline, garnet, quartz and more), from the FGAA-reviewed Gem Data Tables. Accepts trade names — "sapphire" resolves to corundum, "tsavorite" to garnet.
    compare_gemsSide-by-side physical properties of two gem species with a plain verdict on which is harder, and a note on toughness — the half of durability the hardness scale does not show. Good for "sapphire or diamond for an everyday ring".
    birthstone_for_monthThe modern and traditional birthstones for a month, from the FGAA-reviewed table, with a link to The Birthstone Handbook for history, treatments to expect and buying guidance. Accepts a month name or number.
    gem_care_guideWhether warm soapy water, an ultrasonic cleaner or a steam cleaner is safe for a given gemstone, plus everyday-wear notes, from the FGAA-reviewed care table. Covers sapphire and ruby, diamond, emerald, opal, pearl, tanzanite, tourmaline and more.
    get_gem_productFull detail for one Ministry of Gems product by handle or URL: specifications, description, price in AUD, availability, variants, images, the Digital Gemstone Passport link for loose stones, and a direct checkout link. Use after search_gem_inventory.
    lab_report_checkThe issuing laboratory's own verification page and a four-step checklist for confirming a gemstone or diamond grading report — GIA, IGI, GRS, SSEF, Gübelin, AGL, Lotus, GIT, HRD, GCAL and others, including the coloured-stone laboratories diamond tools omit. Explains what "FGAA" means and flags unrecognised lab names. Routes to the lab; does not verify the report itself.
    faceup_size_estimateApproximate face-up millimetre dimensions for a stone of a given species, shape and carat weight — and, unlike diamond-only calculators, corrected for specific gravity, so a 2 ct sapphire, spinel, emerald or opal is sized correctly rather than as if it were diamond. Shapes: round, oval, cushion, emerald, pear, marquise, princess, radiant, heart, trillion.