The gap between a coin selling for £12 and the same coin fetching £85 almost always comes down to three things: a weak title that search ignores, a description that fails to justify the price, and photograph angles that leave doubts in a buyer's mind. This prompt fixes all three — and five more things most hobbyist sellers never think to include.
AI tools like ChatGPT, Gemini and Claude have access to vast numismatic knowledge and eBay listing best practices. The trick is knowing how to ask the right questions in the right order. That's exactly what this prompt is engineered to do.
What the Prompt Covers
The prompt is structured into seven sections, each targeting a specific part of the selling process:
Condition Assessment & Grade
Standard UK grade (EF, UNC, BU etc.) with specific observations that justify your asking price.
Market Appraisal (2026)
Estimated auction range and a recommended starting bid or reserve, anchored to comparable recent sales.
Alternate Sales Strategy
Buy It Now price, Best Offer floor and a net return estimate after eBay fees.
Optimised Title & Description
80-character keyword title and a professional description with mintage facts, history and condition notes.
Technical Item Specifics
Pre-filled eBay fields — Year, Denomination, Era, Composition, Mint, Grade and more.
Authentication & Photography
Counterfeit tells to check, plus the exact shot list and lighting setup to reassure high-value bidders.
Secure Shipping
The exact Royal Mail service, insurance level and packaging method required to protect yourself.
Compatible AI Tools
This prompt works with any vision-capable AI. Paste it alongside your coin photograph into any of the following:
Shoot on a grey card background under natural daylight or a 5500K LED panel. Capture both sides plus any edge lettering. A 12MP smartphone in portrait mode is more than sufficient — but the richer the photo, the richer the AI output.
The Prompt — Copy & Use
Attach a clear photograph of your coin, then paste the entire prompt below into your chosen AI tool. Do not modify the structure — it is engineered to produce output in a specific order that minimises hallucination and maximises listing quality.
I have attached a photograph of a collectible UK coin. Please act as an expert numismatist and seasoned eBay power seller. Analyse the image carefully, then produce a complete, ready-to-use eBay Seller's Success Kit. Deliver the entire response in a single reply using the seven numbered sections below. Where data cannot be determined from the image alone, clearly state what you are estimating and why. — SECTION 1: Condition Assessment & Grade — • Assign a standard grade using UK/Sheldon scale terminology (P, F, VF, EF, UNC, BU, Proof). • List the specific grading observations you made — lustre, strike sharpness, contact marks, rim integrity and any toning. • Note any cleaning, polishing, or artificial toning that would affect desirability. • State your confidence level (High / Medium / Low) and what additional images, if any, would improve accuracy. — SECTION 2: Market Appraisal (2026) — • Provide a realistic estimated hammer price range for a standard 7-day eBay auction. • State a recommended Starting Bid or Reserve Price, with your reasoning. • Reference two or three comparable recent sold listings (describe them specifically — date, grade, realised price) to anchor the valuation. • Flag any factors — Royal Mint year variants, error coins, low mintage, anniversary status — that meaningfully push value up or down. — SECTION 3: Alternate Sales Strategy — • Recommend a Buy It Now (BIN) price and a Best Offer floor price. • Provide a net-return estimate after eBay's standard 12.8% + 30p final value fee, so the seller knows actual take-home. • Suggest the ideal listing duration and whether a Promoted Listing ad rate (typically 2–5%) would be worthwhile. • Advise whether auction or BIN is more appropriate for this specific coin and market conditions. — SECTION 4: Optimised eBay Title & Description — • Write a keyword-optimised TITLE of exactly 80 characters maximum — front-load the most searched terms (denomination, year, monarch, grade; use "RARE" or "LOW MINTAGE" only if genuinely warranted). • Write a professional DESCRIPTION covering: full coin identification, mintage figures, historical or commemorative context, current grade and notable condition details, and what makes this coin desirable to a collector. • Include a short "What You Are Buying" paragraph and a "Seller Guarantee" line to build buyer trust. • End with a natural keyword footer (comma-separated terms a buyer might search) for eBay's Cassini search engine. — SECTION 5: Technical Item Specifics — • Produce a clean two-column table of eBay Item Specifics, pre-filled with the correct values: Year of Issue | Denomination | Country/Region | Monarch/Era | Composition | Diameter (mm) | Weight (g) | Mint | Mintage | Grade | Certification | Strike Type | Edge Type | Theme/Subject — SECTION 6: Authentication & Photography Guide — • List the specific counterfeit or replica tells to check for this particular coin — design details, weight tolerance, edge lettering, security features. • Provide a Photography Shot List with exact angles and lighting: – Obverse (face-on, full frame) – Reverse (face-on, full frame) – Edge (rolling shot or three-point composite) – Any mint marks or privy marks (macro) – Notable lustre, toning or contact marks (raking light) – Coin alongside a ruler for size reference • Recommend background colour and lighting setup (e.g. "grey card, single 5500K LED at 45°"). — SECTION 7: Secure Shipping Recommendation — • Recommend the specific Royal Mail (or courier) service appropriate to the coin's estimated value. • State the required insurance/compensation level and how to claim if lost or damaged. • Advise on correct packaging — coin capsule, padded envelope vs. small parcel box, bubble wrap layering. • Confirm whether Signature on Delivery is needed to protect against false "item not received" claims. Please format each section with a clear heading and use bullet points within sections. Keep the language professional but accessible to a UK hobbyist seller. Do not add disclaimers between sections — deliver the full kit in one clean, scannable response.
Getting the Best Results
Both Sides + Edge
Upload three images where possible — obverse, reverse and an edge crop. More visual data means a more accurate grade and valuation.
Tell It What You Know
Prefix the prompt with any facts you already have: "This is a 1935 Crown, I believe EF, bought from an estate sale."
Paste Sections Directly
The title, description and Item Specifics are formatted to paste straight into eBay's listing form with minimal editing.
Ask for Revisions
Not happy with the title? Reply "Rewrite the title targeting collectors of George VI crowns" — the AI refines without losing the rest.
AI valuations are a useful starting point, not a substitute for professional appraisal. For coins likely worth over £500, cross-check on eBay sold listings (filter: Sold Items) or Spink auction archives before listing.
Why Most Coin Listings Leave Money on the Table
Serious eBay coin buyers are sophisticated. They search by specific terms — "1953 crown EF", "2009 Kew Gardens 50p BU" — and they scroll past vague listings instantly. A title like "Old silver coin — great condition" loses to "1953 Elizabeth II Coronation Crown EF — Low Mintage UK Coin" every time.
Equally, buyers for higher-value coins need to be reassured before they bid. They want proof of authenticity, photographs that show what an expert would look for, and confidence that the seller will pack and ship correctly. The AI prompt generates all of this automatically — giving every coin you list a professional presentation that builds bidder confidence and supports your asking price.
Looking to Buy UK Coins Too?
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This prompt is updated as AI capabilities improve. Bookmark this page for the latest version. Last updated: February 2026.