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Known Errors

Sacagawea/Quarter Mule

A coin struck with a Washington quarter obverse die and a Sacagawea dollar reverse die. The coin is on a dollar-size planchet with a plain edge.

How to check: The obverse shows Washington's portrait from the quarter design, while the reverse shows the Sacagawea dollar eagle design. The coin is dollar-sized with a plain edge instead of reeded.

$50,000 - $100,000+

Edge Variations

Known mule specimens show variations in edge characteristics depending on which collar die was used during striking.

How to check: Examine the edge carefully. Some examples have a plain smooth edge while others show partial reeding.

Premium based on specific die state

Die State Variations

Different die states exist among the known specimens, with earlier die states showing sharper detail.

How to check: Compare the sharpness of design details to known die state photographs. Earlier strikes show crisper lettering and design elements.

Earlier die states command premium

Quick Checks

Frequently Asked Questions

How much is a Sacagawea quarter mule worth?

Known examples have sold for $50,000 to over $100,000 at auction. A PCGS MS-67 example sold for $155,250. These are among the most valuable modern US coin errors.

How were Sacagawea quarter mules created?

During production at the Philadelphia Mint, a Washington quarter obverse die was accidentally paired with a Sacagawea dollar reverse die. The similar collar sizes made this mix-up possible.

How many Sacagawea quarter mules exist?

Approximately 12-15 examples are known. They were discovered in 2000 when collector Frank Wallis found the first example in a Sacagawea dollar roll obtained from a bank.

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