Our Methodology

Research, sourcing, capability, and correction standards · last reviewed 2026-08-24

Coin identity and buying decisions turn on small details: date, mintmark, variety, surfaces, holder, and grade. This page explains how Coin Curator researches its catalog and guides, separates sourced facts from editorial context, and handles corrections. Coin Curator is an educational research guide, not a grading service, dealer, appraiser, or investment adviser.

Publication and accountability

Guides use organization-level attribution to Coin Curator and do not imply unverified staffing, credentials, or individualized review. The goal is to help a reader identify the coin, understand the tradeoffs, verify primary records, and compare buying routes before spending.

Where our key-date and mintage data comes from

Mintages, key-date designations, varieties, and strike designations (Full Bands, Full Steps, Full Bell Lines, and the like) are compiled from the long-established primary references collectors already trust, and cross-checked against more than one before we publish:

How we handle market context

Coin Curator holds no licensed price guide, and does not operate a live price monitor, a cross-grader comparison system, or a portfolio valuation service. What it does publish, on key and semi-key date pages only, is recent eBay sold prices: a record of completed sales, described below. When a guide discusses a historical sale or time-sensitive market figure, it must identify the source, relevant grade or designation, sale window, and date checked. Otherwise the figure is removed or labeled as general editorial context.

Asking prices, realized prices, price-guide values, and bullion value are different measures and must not be blended without explicit labels. No displayed number should be treated as an appraisal or prediction.

How we collect sold prices

Sold prices appear on key and semi-key date pages only. Both tiers are computed from the reported mintage by the same published rule used everywhere on this site, so which pages carry sold data is reproducible from public figures rather than chosen by hand. Common dates are left out because most trade as type coins, and a search for one specific common date returns mostly rolls and raw lots. Two issues are deliberately excluded even though they qualify: the 1933 double eagle and the 1964-D Peace dollar, because no genuine example of either can lawfully be bought and every listing such a search returns is a replica.

For each of those coins we read eBay's completed-sales results and keep only listings that pass every one of these tests. A listing must name PCGS, NGC or ANACS, the three services whose certification lookups this site links to. It must carry a numeric Sheldon grade whose letters and number agree, so a garbled “MS45” is discarded rather than guessed at. It must name the exact year, mint and, where one exists, the exact variety: a Philadelphia issue is matched by the absence of a branch mintmark, and a 1909-S VDB cent is never counted as a plain 1909-S. And it must not read as a proof, a coin in a “Details” or “Genuine” holder, a cleaned or damaged coin, a replica, a plated or mounted piece, or a roll, lot or multi-coin bundle. Each of those sells at a price that would not describe the coin on the page.

Some counterfeits carry a title with nothing wrong in it, so those are caught by arithmetic rather than wording. A sale priced below what the same date and mint fetches in a lower grade cannot be the same coin, because grade only ever adds value. Two 1889-CC Morgan dollars sold in one 90 day window titled as ANACS MS70 at $150 each, while genuine examples of that date were selling for $1,350 in VG10 and $49,995 in MS63. Both $150 sales were discarded on that rule, and neither reached the page.

Surviving sales are grouped into four grade bands, because a coin's grade drives most of what it is worth and a single median across all grades would describe none of them: Good to Fine, Very Fine to Extremely Fine, About Uncirculated, and Mint State. Four rather than three is a deliberate correction. One combined circulated band spanning G4 to XF45 put a 1921-D Walking Liberty half, which sells around $150 in G4 and thousands in XF45, under a single median that described no real coin. A band is published only if it has at least three sales; below that a median is an anecdote. Each band shows the median after removing statistical outliers, the full untrimmed low and high so the spread is visible, the number of sales it rests on, and links to the most recent listings so you can read the originals. Sales older than 90 days are dropped.

Two rules govern what happens when the collection fails. A search that returns nothing never erases prices we already published, because a blocked fetch and a quiet market look identical at that moment, and stale-but-real beats fresh-and-empty. And if the bands for a coin come out in an impossible order, with a worn example median above a mint state one, we take that as proof something which is not that coin got through the filters, and the page publishes nothing for it until the next run.

These figures are a record of what specific certified coins sold for. They are not a price guide, not an appraisal, not a valuation of any coin you own, and not a prediction. Coin Curator does not grade, authenticate, or appraise coins.

How we keep guides current

Every guide carries a visible "Last updated" date, and the same date is written into each article's structured data so search and answer engines can see how fresh the content is. Our most recent site-wide review was 2026-08-24. When mintage figures, price ranges, or grading-service practices change, we revise the affected guides and bump that date.

Editorial independence

Coin Curator is reader- and affiliate-supported, but affiliate status never decides which coins, dates, dealers, or grading services we recommend. We link to non-affiliate sources (PCGS, NGC, Heritage, Stack's Bowers) whenever they help a collector, and we flag affiliate links plainly. Full details are on our affiliate disclosure page.

How we use AI

We use AI tools to help research, draft, and maintain parts of this site. A person reviews what gets published and we fix errors when we find them, but AI-assisted content can still be wrong or out of date, so confirm the details that matter on the seller's own listing before you buy. We do not publish AI-generated reviews or testimonials. No AI system reads or processes anything you submit to us.

Corrections

Found a mintage, market figure, source, or attribution that looks wrong? Use the corrections path. A material correction updates the visible review date after the change is checked; cosmetic edits do not create a false freshness signal.

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