2010-S Yellowstone, Silver Proof

The 2010-S Yellowstone Silver Proof is the second entry in the inaugural year of the ATB silver proof slate, struck at San Francisco on 90% silver planchets at 6.25 grams. Don Everhart's reverse renders the Old Faithful Geyser in mid-eruption with a bison standing in the foreground, the same composition carried by the year's clad proof and circulation strikes but rendered in .900 fine silver alongside the 1992 silver-proof convention. The Mint reported 585,401 silver proof sets sold for 2010, the production anchor that fixes the print run on every silver entry that year. The geyser-and-bison combination remains one of the more compositionally busy reverses in the ATB silver proof run, with the relief on both subjects giving the dies more device area to frost.

Authentication on the issue begins with weight: 6.25 grams for silver, 5.67 grams for clad, a half-gram difference any jeweler's scale can resolve. The reeded edge runs solid silver around the perimeter without the reddish copper-core line a clad piece shows when tilted. PCGS, the Professional Coin Grading Service, and NGC, the Numismatic Guaranty Company, mark every silver insert with the words Silver or the S/Ag abbreviation alongside the standard proof designation. Cameo (CAM) and Deep Cameo (DCAM) are the two contrast tiers, and DCAM is the dominant outcome on the coin because the working dies receive a chemical etch that frosts the raised relief before each press run. Strike diagnostic points include the texture in the rising steam plume, the bison's mane and shoulder hump, and the device-to-field transition along the geyser cone.

The market treats the issue as a year-set or design-set component priced against the silver-content floor, not as a standalone rarity target. PR69-DCAM examples trade for a small premium over spot value at the 0.1808 ounce silver-weight figure, and PR70-DCAM examples sit a tier above that with the registry-driven spread modest by historical proof standards. The Yellowstone design tends to attract a slightly stronger single-design buyer base than the more abstract ATB landscapes because the geyser-and-bison composition reads instantly to non-specialist eyes. For the broader story of the ATB Silver Proof program and the series' production arc, see the Washington ATB series history.