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: