Imagine pulling a coin from your collection and discovering it’s worth nearly $200,000.
That exact scenario happened because of one of the most famous modern minting mistakes in U.S. history — the Washington Quarter / Sacagawea Dollar Mule Coin.
Only three confirmed examples exist, making this error coin one of the rarest and most valuable modern U.S. coins ever discovered. Below is a step-by-step breakdown explaining what it is, why it’s valuable, and how you can identify one.
Step 1: What Is a Mule Coin?
In numismatics, a mule coin is created when:
The obverse (front) die and
The reverse (back) die
come from two completely different coins.
These errors are extremely rare because U.S. Mint quality controls are designed to prevent mismatched dies. When one slips through, it becomes an instant legend among collectors.
Step 2: The Famous 2000 Quarter / Sacagawea Mule Explained
This historic error combines two different coins:
• Front (Obverse): Washington Quarter
• Back (Reverse): Sacagawea Dollar eagle 
Because the reverse die belongs to a dollar coin, the final piece is larger, heavier, and smoother than a normal quarter.
Step 3: Compare a Normal Quarter vs. the Mule Coin
| Feature | Normal Quarter | Quarter Mule Coin |
|---|---|---|
| Diameter | 24.26 mm | 26.50 mm (Dollar size) |
| Weight | 5.67 g | 8.10 g |
| Edge | Reeded | Plain (smooth) |
| Reverse | Quarter eagle | Sacagawea eagle |
| Mint Mark | D (Denver) | D (Denver) |
Once you know these differences, the mule coin becomes instantly recognizable.
Step 4: How Much Is the Quarter Mule Coin Worth?
Because only three authenticated coins exist, prices remain in the six-figure range.
Verified Auction Results
• $195,000 – PCGS MS66 (Heritage Auctions, 2023)
• $192,000 – NGC MS67 (Stack’s Bowers, 2022)
• Private Sale: ~$200,000 (NGC MS67, 2024)
Certified coins sell 200–300% higher than ungraded examples.
Step 5: How Did This Error Happen?
In 2000 at the Denver Mint, a Washington Quarter obverse die was mistakenly paired with a Sacagawea Dollar reverse die inside a dollar press.
This explains:
Larger size
Smooth edge
Heavier weight
Experts believe 5–10 may exist, but only three have been officially confirmed.
Step 6: How to Identify a Possible Mule Coin
Use this checklist before getting too excited:
Larger than a quarter
Weighs about 8.10 grams
Smooth edge (no reeding)
Sacagawea eagle on the reverse
Tip: Compare it side-by-side with a regular 2000-D quarter.
Step 7: How to Avoid Counterfeits
Because of its value, fake mule coins exist.
Gold-plated coins
Incorrect size or weight
Visible seams or tooling marks
Authentic examples are not altered quarters — they were struck that way at the Mint.
Step 8: Where These Coins Have Been Found
Yes — more could still be out there 
Best Places to Search:
• 2000-D U.S. Mint Sets
• Denver Mint quarter rolls
• Estate sales and old collections
Recent report: One collector allegedly found a mule coin in an unopened mint set purchased for just $5.
Step 9: What to Do If You Find One
If you think you’ve discovered a mule coin:
Do not clean it
Handle by the edges only
Take clear photos (front, back, edge)
Store securely
Then submit it to:
• PCGS or NGC for grading
• XRF testing for metal verification
Step 10: Selling a $195,000 Coin
For coins of this caliber, use top-tier auction houses:
• Heritage Auctions
• Stack’s Bowers
• Legend Rare Coin Auctions
Certified examples consistently sell for up to 3× more.
Expert Opinion
“The Quarter-Dollar Mule is the perfect combination of rarity, beauty, and minting mystery — a true modern icon.”
— Dr. Eleanor Vance, Chief Numismatist
