1795 Silver Plug

The Silver Plug variety of the 1795 Flowing Hair dollar documents one of the earliest known quality-control fixes in U.S. coinage. When workers at the fledgling Philadelphia Mint found a finished planchet that fell below the 416-grain legal weight standard, they drilled a small hole near the center and tapped in a tiny silver dowel before striking. The press flattened the dowel and pushed metal outward, leaving a faintly outlined disc roughly 8 millimeters wide visible on both faces of the coin. Numismatists have identified only five die marriages of the 1795 Flowing Hair that are confirmed with this remediation: B-1 (BB-21), B-3, B-4, B-7 (BB-18), and B-9, spanning both Two Leaves and Three Leaves reverse types. The same expedient was used on a portion of the 1794 emission, including the SP66 Cardinal-Contursi specimen recognized as the finest 1794 dollar known. Once Adam Eckfeldt's planchet-rolling improvements stabilized strip thickness, the practice ended.

Authenticating a genuine Mint plug requires careful examination under angled light and 10x magnification. A real plug shows a faint circular seam around part or all of its circumference, often with a subtle color shift where the inserted silver's alloy differed slightly from the host planchet. The decisive test is that design devices (Liberty's hair, the eagle's breast feathers, parts of the wreath) flow continuously across the boundary, proving the plug was in place before striking. Wavy adjustment marks across the neck or jaw frequently accompany the feature. Both PCGS (Professional Coin Grading Service) and NGC (Numismatic Guaranty Company) recognize the variety on the holder, and attribution follows the Bowers-Borckardt reference (BB), the standard 1993 catalog by Q. David Bowers and Mark Borckardt that supplanted Bolender for early dollars. Market-treated "false plugs" do exist, so independent third-party certification is essentially mandatory at this level.

Population data places the Silver Plug among the trophy tier of American silver. PCGS estimates approximately 250 examples survive across all grades, with only 6 documented at Mint State and 2 at MS65 or better. The benchmark sale is the Lord St. Oswald, D. Brent Pogue BB-18 in PCGS MS65+, which realized $705,000 at Stack's Bowers in September 2015. For deeper context on the design and the two-year emission, see the Flowing Hair Dollar series history.