How to keep a coin collection inventory

Why keep a coin inventory

Coins are small, numerous and easy to mix up. An inventory tells you which dates and mint marks you still need for a set, where each coin is stored, and what you paid. It saves time at coin shows, and it gives your family a clear picture of the collection if they ever need it.

It also gives you a record for insurance. Many homeowners policies limit coverage for coins and other collectibles unless they are scheduled separately, and the U.S. Mint suggests checking that your insurance covers the full replacement cost of a collection kept at home. A list with photos is the starting point for that conversation with your insurer.

For setting up categories and storage locations across several kinds of collections, see our general guide to cataloging a collection. This guide covers the fields specific to coins.

Year, mint mark and variety

Identify each coin before you grade it. The basic identity is the country, denomination, type or design, year and mint mark. Two coins of the same year can differ in value because they were struck at different mints, which is why the mint mark matters so much.

On US coins, the mint mark is a small letter showing where the coin was struck: P for Philadelphia, D for Denver, S for San Francisco and W for West Point, with historic marks such as CC for Carson City and O for New Orleans. Some coins have no mint mark at all, including Philadelphia cents. Its position varies by design, so check a reference for each series.

Then note any known variety, such as a doubled die or an overdate, if a reference lists one for that date. A good reference book or a grading service’s online price guide covers dates, mint marks and varieties together.

Grading with the Sheldon scale

Most US coins are graded on the Sheldon scale, a 1 to 70 numeric system developed by Dr. William Sheldon in the late 1940s and later adopted for all US coins. Grades from 1 to 58 cover circulated coins, and 60 to 70 cover Mint State coins that never circulated. Proof coins use the same numbers with a PR or PF prefix.

1. Poor to Good (P-1 to G-4)

   Heavily worn. In Good, the main design is visible but parts are worn flat.

2. Very Good to Fine (VG-8 to F-12)

   More detail remains. In Fine, about half the detail is worn but lettering is sharp.

3. Very Fine to Extremely Fine (VF-20 to EF-40)

   Moderate to light wear on the highest points, with most detail sharp.

4. About Uncirculated (AU-50 to AU-58)

   Only traces of wear on the high points, with much of the original luster.

5. Mint State (MS-60 to MS-70)

   No wear from circulation. Higher numbers mean fewer marks and better luster and strike; MS-70 shows no imperfections under 5x magnification.

Raw and certified coins

A raw coin is one that has not been professionally graded. Third-party grading services, the best known being PCGS and NGC, examine a coin, assign a grade and seal it in a tamper-evident holder, often called a slab, with a certification number on the label. Both services let you look up a certification number on their websites.

For a certified coin, record the service, the certification number and the grade exactly as printed. For raw coins, record your own grade and mark it as such, since self-grading is an estimate. Whether professional grading is worth the fee depends on the coin, and a dealer or the service itself can explain the options.

Handling and storage

The U.S. Mint’s advice is short and worth following. Hold coins by the edges over a soft surface, ideally with cotton gloves. Do not clean or polish them; cleaning can reduce a coin’s value, and natural toning is generally preferred to a stripped surface.

• Store coins in acid-free holders, flips, albums or capsules that are free of PVC, which can leave a sticky green residue on coins over time.
• Keep them cool and dry, away from sudden changes in temperature and humidity.
• Keep modern sets in their original packaging and certificates with the coins.
• Use numbered albums, pages and boxes so each coin’s location is specific, such as Safe / Album 2, and note the page or slot in the item’s description.

Fields to record for each coin

A consistent set of fields makes it easy to sort by series and see gaps.

• Country, denomination and type or series
• Year and mint mark
• Variety, if any
• Grade, and whether it is your own grade or a certified one
• Grading service and certification number for slabbed coins
• Composition and weight, for silver and gold coins
• Purchase price, date and source
• Storage location down to the album page or box

How Allventory fits a coin collection

Allventory’s standard Collectibles & memorabilia category includes Year / era, Edition / variant, Grade / condition and Authentication / certificate. You can add attributes to it, or create a Coins category with exactly the fields above.

1. Category attributes

   Add Denomination, Mint mark and Grading service as dropdowns, Year and Sheldon grade as numbers, Weight as a number in grams, Certification number as text and Certified as yes or no. The Home plan allows up to 15 attributes per category, Portfolio 30 and Professional 50.

2. Several coins from one photo

   Lay out a few coins or slabs and photograph them together. Allventory suggests a separate item for each, with names, categories and estimated values to review before saving. Estimated values are AI suggestions, not appraisals or grades.

3. Albums and boxes as locations

   Name locations as paths, such as Safe / Album 2 or Safe / Box 1, and filter by Safe to see everything inside it.

4. Photos and certificates

   Attach obverse and reverse photos, receipts, certificates and dealer invoices, up to 20 files per item.

5. Tags for your sets

   Use tags such as Need upgrade, Duplicate or For trade, and apply them to many coins at once.

6. Export for your records

   Export the list to CSV on every plan, or Excel and insurance supporting documents on paid plans, to share with your insurer or your family.