2013-S Great Basin Proof

San Francisco struck 1,232,104 pieces of the 2013-S Great Basin clad proof for collector distribution inside the year's two proof products. Don Everhart's reverse renders a single Great Basin bristlecone pine, the species that produces the oldest known non-clonal organisms on earth. The tree's gnarled trunk and exposed root structure fill most of the design field, and the engraving relies on dense linework to translate the wind-shaped wood texture into the proof finish. The issue is the third of five 2013 releases and one of the few ATB reverses where a single living organism, rather than a landscape or built structure, occupies the entire design space.

Proof finish on the issue follows the San Francisco standard: mirrored fields struck from polished planchets against dies that have been frosted in chemical baths before each press run. Cameo (CAM) and Deep Cameo (DCAM) are the two contrast designations PCGS, the Professional Coin Grading Service, and NGC, the Numismatic Guaranty Company, apply on top of the numeric grade. DCAM is the default outcome on the issue and grade distribution clusters at PR69-DCAM and PR70-DCAM in the major service pop reports. The bristlecone's wood-grain detail is the strike diagnostic point: a properly struck example shows clean texture across the trunk's deepest hollows, while a weak strike flattens the texture into a smooth, undefined surface. Counterfeit risk is essentially nil at the price point.

The issue trades as a year-set or design-set filler at the bottom of the modern proof market. A raw certified PR69-DCAM example trades for a few dollars over the cost of breaking up a sealed 2013 Proof Set, and PR70-DCAM examples in PCGS or NGC holders carry a small premium that has flattened as ATB proof registry-set competition has slowed. The Great Basin reverse draws steady appreciation from collectors interested in numismatic depictions of natural science and biology, and the bristlecone subject pairs well in topical collections with the 2018 Apostle Islands lighthouse-and-fall-color design that uses similar dense linework. For the broader story of the ATB proof program and the series' production arc, see the Washington ATB series history.