Australian error coins are among the most fascinating and valuable collectables in the numismatic world.
While most coins are struck perfectly, occasional mistakes at the mint can create rare variations that collectors actively hunt.
Some of these “errors” can be worth hundreds or even thousands of dollars, depending on rarity and condition.
In this guide, we break down the most common Australian coin errors, how to spot them, and what they could be worth.
What is an error coin?
A coin error occurs during the minting process when something goes wrong, resulting in a coin that differs from the intended design.
These aren’t post-mint damage (like scratches or dents). True errors happen during production, with most modern Australian coin errors originating from the Royal Australian Mint.
Australian error coins can range from minor mint flaws to rare pieces worth thousands.
Types of Australian Error Coins
1. Off-Centre Strikes
When a coin isn’t properly aligned during striking, part of the design is missing.
What to look for:
- Design shifted to one side
- Blank crescent-shaped area
Value:
- Minor: $50–$150
- Major: $300–$1,000+
2. Double Strikes
A coin is struck more than once, creating overlapping designs.
What to look for:
- Ghosting or duplicated features
- Misaligned second impression
Value:
- $200–$2,000+ depending on clarity
3. Bullseye Errors
A “bullseye error” is a term used by collectors to describe rare Australian $2 coins where the coloured commemorative design is mistakenly applied to the obverse (head side) – around the Queen’s portrait – instead of the reverse.
What to look for:
- Coloured ring or design surrounding the Queen’s effigy
- Reverse may be missing colour entirely
Value:
- Typically $500–$2,000+
- Strong, verified examples can exceed this
How to tell if it’s real (or fake):
Likely genuine:
- Colour sits cleanly within design boundaries
- Finish matches official mint application (even, not blotchy)
- No paint bleed, brush marks, or surface buildup
Likely fake / altered:
- Colour looks painted or sits unevenly
- Brush strokes, pooling, or incorrect shade
- Colour easily scratches or flakes
- Applied over dirt, damage, or existing wear inconsistently
4. Brockages (Mirror Image Errors)
A previously struck coin sticks to the die and imprints a mirror image onto the next coin.
What to look for:
- One side appears mirrored/incuse
- Missing normal design on one face
Value:
- $1,000–$5,000+ for strong examples
5. Mule Errors (Wrong Die Pairings)
Two dies that were never meant to be paired are used together.
What to look for:
- Design elements from different denominations
- Unusual rim or alignment
Value:
- $3,000–$10,000+
Are Coin Errors Always Valuable?
No, this is where many people get it wrong.
Damage ≠ error
Coins that are:
- Scratched
- Bent
- Worn down
- Corroded
…are usually worth face value only.
True mint errors are:
- Structurally part of the coin
- Consistent with minting faults
- Often confirmed by experts or grading services
How to Tell if Your Coin Error Is Real
Before getting excited, check:
- Is the feature raised or incuse (not scratched)?
- Does it match known error types?
- Is the coin otherwise genuine?
If unsure, it’s worth getting a professional opinion.
Should You Get Error Coins Graded?
Yes, especially for higher-value pieces.
Grading through services like PCGS:
- Confirms authenticity
- Increases buyer confidence
- Can significantly increase value
Where to Sell Australian Coin Errors
You have three main options:
- Private sale
- eBay
- Auction (best for rare errors)
High-quality error coins perform strongly at auction, where multiple bidders compete.
Final Thoughts
Australian error coins sit at the intersection of rarity, curiosity, and value. While not every unusual coin is valuable, genuine mint errors can command serious prices, especially when verified and presented correctly.
If you’re unsure whether your Australian error coins are valuable, getting expert advice is key.
Have an Error Coin?
If you think you’ve found something unusual, we can help.
👉 Get a professional appraisal from the team at Roxbury’s Numismatics
👉 Or consign to one of our upcoming auctions for maximum exposure
