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Coin Error Types: Die Breaks and What Causes Them
Learn what die breaks on coins are, how chips, cracks and cuds form, how to tell them from damage, and how they fit among the main coin error types.
Coin Types & Authentication
Error Coins
6 guides, starting with Coin Error Types: Die Breaks and What Causes Them.
Coin Edge Designs: Reeded Plain and Lettered Edges
A beginner's guide to coin edge designs, from plain and reeded edges to lettered and decorated edges, why mints use them and what edge errors look like.
Double Dated Coins and Doubled Dies Explained
Double dated coins can mean overdates, doubled dies or the 2026 dual-date US designs. Learn the differences, famous examples and what may be worth checking.
Minting Errors on UK £2 Coins: What to Look For
A cautious guide to minting errors on UK £2 coins, including the Lord Kitchener mule claim, what genuine errors look like, and how to check a coin.
Missing Clad Layer Errors: How to Spot and Value Them
What is a missing clad layer on a coin? Learn how the error forms, how to identify it by colour, edge and weight, and what affects its value.
Two Toned Coins: Natural Toning vs Damage
Two toned coins can mean bimetallic coins or coins with natural toning. Learn how toning forms, how it differs from damage, and why you should not clean coins.
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