The following mint errors sold in the November 2025 US Coins Signature® Auction #1387.
Images Courtesy of Heritage Auctions, HA.com
'Two-Tailed' Washington Quarter Mule, MS64
Struck With Two Reverse Dies
Previously Unknown Specimen
Sold For: $84,000.00
Undated 25C Washington Quarter Mule -- Struck With Two Reverse Dies -- MS64 NGC. Many collectors consider mules -- coins struck with mismatched dies -- to be the proverbial Holy Grails of U.S. coin errors. Only a few dozen are collectively known across all types, series, and denominations. Perhaps the most famous mule is the Sacagawea dollar struck with a Washington State quarter obverse die. Approximately 18 examples of that specific mule exist. Others include various Lincoln cents struck with Roosevelt dime reverses. But the rarest of the mules are those "double sided" coins struck with two obverse or two reverse dies. One of these is the clad Washington quarter struck with two reverse dies, of which only a handful are known.
The first of these Washington quarter reverse die mules was discovered in 2001, and later that year a second example was reported. Both of those coins were subsequently certified by NGC as MS63. More than a decade later, in 2017, PCGS certified another piece in MS62. A similar piece, certified MS66 NGC as struck with two reverse dies with an additional indent, was offered in our auctions in 2006.
The present piece, certified by NGC as MS64, is a new discovery of this magnificent mule. It was acquired by our consignor a number of years ago as part of an estate sale purchase, where it was in a collection of other U.S. coins. This mule was raw at the time, housed in a simple paper envelope, and was subsequently certified at NGC. Unfortunately, its origins prior to appearing in that estate offering are unknown. Existing scholarship on these "two-tailed" mules is that they were struck at the San Francisco Mint during the 1965-1967 coinage era when mintmarks were not used, but concrete details are yet to be unearthed.
The other two-tailed quarter mules were not available for comparison by this cataloger, but studying images of two of the other pieces suggests this MS64 coin was struck with the same dies, and thus likely was struck at the same time. The facing side as slabbed in the NGC holder is from the worn and flow-lined die, while the opposite side is from the slightly reflective die with heavy striations in the fields. It also has a perfect coin alignment. A generally sharp strike adorns each side, though some weakness appears on the eagle's wing tips and on the final A in AMERICA. Eye appeal is certainly spectacular for the grade.
Ex: Purchased raw from an estate, later certified at NGC; consigned to Heritage's November 2025 Dallas Signature Auction (9/2025).
1979-P Anthony Dollar, MS67
Struck on a 1978 Quarter
Double Denomination Error
Sold For: $10,200.00
1979-P Susan B. Anthony Dollar -- Overstruck on a 1978 25C, Double Denomination -- MS67 NGC. Although cents struck on dimes are encountered from time to time, other double denomination mint errors are challenging to find, especially combining obsolete types. This impressive Superb Gem displays a bold date and mintmark for the dollar strike. The quarter date is faint but essentially complete, located between 3 and 4 o'clock on the reverse of the dollar strike. Washington's profile is surprisingly clear and complete. From the quarter strike, most of the eagle's left wing is prominent within the upper outline of the Anthony bust. A hint of tan-gold toning visits both sides of the virtually pristine surfaces.
Ex: Misfits Collection of Error Coinage, Part 2 (Heritage, 12/2022), lot 93243.
