Rotated die / die rotation Coin Errors
What is a rotated die / die rotation error?
UK coins are struck with "medal alignment" — when you flip the coin top-to-bottom, the obverse and reverse should both be upright. A rotated die error happens when one of the dies was set in the press at an angle, so flipping the coin reveals a tilted reverse. Severity is measured in degrees: 15° rotations go unnoticed; 90°, 180° (US "coin alignment") and 270° rotations are clearly visible.
How to spot one
- Hold the coin obverse-up, then flip top-to-bottom (not side-to-side). The reverse should be upright.
- Any visible tilt is a die rotation. Use a protractor or eye-grid to estimate degrees.
- Major rotations of 90°+ are dramatic; 15-30° rotations require careful comparison.
- Confirm by comparing two examples of the same coin year side by side.
Authentication
Rotation errors are usually genuine — counterfeiters rarely target this error type. Photograph both sides with the same orientation reference for documentation.
Famous UK examples
Common; major (>90°) rotations on commemoratives reach £100+.
Bimetal £2 rotations are scarcer due to two-piece assembly.
Key-date UK coins worth examining
Errors on key-date coins compound rarity — the host coin is already scarce, and the error multiplies the value. Browse the rarest UK coins in our catalogue: