Online bidding has opened in Stack’s Bowers Galleries’ Sept. 12 auction for one of the most unique offerings ever presented on behalf of the United States Mint: eight Sacagawea gold dollars that bridge numismatics with space history.
Announced last month, the auction already has bids ranging from $48,000 to $100,000, but final prices are expected to climb significantly higher, with Stack’s Bowers citing a 1999 value estimate of "approximately $1 million" for each space-flown coin. Final live bidding begins at 9:00 a.m. PDT (12:00 p.m. EDT) on Sept. 12 at the firm’s Costa Mesa, California headquarters and online.
First Public Offering of Space-Flown Sacagaweas
Originally, 39 Sacagawea dollars were struck in 22-karat gold, but only the 12 finest were selected to fly aboard Space Shuttle Columbia in July 1999; the rest were destroyed. Commanded by Col. Eileen Collins, the mission marked the first shuttle flight led by a woman. During their 1.8 million-mile journey — about 80 orbits of Earth — these proofs served to raise awareness of the Sacagawea dollar, which entered circulation the following year.
Each coin carries the finely detailed "engraved tail-feathers" reverse, the same design found on the scarce "Cheerios" dollars, which was used only on the earliest Sacagawea coins before being replaced with a lighter design.
"Furthermore, they are the only federally-issued U.S. coins to be struck exclusively for spaceflight," Stack’s Bowers notes. "While other coins have traveled into space — including the famous ‘space penny’ 1793 Wreath Cent Stack’s Bowers Galleries sold for $82,250 in May 2015 — no others were produced specifically with orbit in mind."
After their return from space, the coins were secured at Fort Knox and displayed publicly just once, at the 2007 ANA World’s Fair of Money in Milwaukee. With seven now crossing the block, five will remain in the Mint’s collection, with two reserved for museums and special-event displays.
"The remaining five coins will be kept as part of the US Mint’s archived permanent heritage collection," the Mint stated. "The United States Mint will set aside two coins to entertain requests to display at special events, museums, and other institutions."
All seven have been certified by Professional Coin Grading Service (PCGS) as Proof-69 Deep Cameo, with current bids ranging from $65,000 to $100,000.
The First 2025-W Sacagawea Joins the Lineup
Alongside the space-flown group is the first-struck 2025-W Sacagawea dollar in 24-karat gold. Issued for the series’ 25th anniversary, it is part of the 7,500 half-ounce proof coins released by the U.S. Mint on July 31 and sold out quickly at $2,175 each, though this inaugural piece was held back as the #1 example.
Certified by PCGS as Proof-70 Deep Cameo, it currently carries a bid of $48,000.
Online Bidding at Stack’s Bowers
These pieces, never released as coinage, will be monetized as legal tender upon sale, with $1 of each final price representing face value.
Stack’s Bowers Galleries is also waiving the Buyer’s Premium for all eight Sacagawea dollars, so the hammer price is the total due from the winning bidder, aside from shipping.
Online bidding for the coins is hosted on the Stack’s Bowers Galleries auction page.
