Stack’s Bowers Galleries to Offer John Burger-regulated Brazilian 6,400-reis Gold Coin in Spring 2023 Auction

No, King Joseph I’s eye isn’t bugging out on this 1762/1-R Brazilian 6,400-reis. The coin was plugged and stamped by John Burger, a New York assayer and coin regulator and contemporary of the famed Ephraim Brasher. Before, during and after the American Revolution in what would become the United States, a coterie of assayers “regulated” gold coins – assaying and then raising or lowering their weight to the necessary level to serve in. In this time, before the establishment of the U.S. Mint, such pieces filled an acute need for coinage of a standard weight. In our Official Auction of the Whitman Coin & Collectibles 2023 Spring Expo, we are pleased to be presenting this beautiful example, graded AU-55 Countermark Unc Details by NGC, a piece that was modified to serve as an $8 coin then later clipped to meet a lighter West Indian standard.

Referred to as “Half Joes” – a reference to the Portuguese rulers Johannes (to 1750) and Josephus (1750-1777) whose portraits appear on the obverse – the gold 6,400-reis coin was widely used in colonial America. Clipping, shaving, “sweating” (a practice in which coins were placed in a bag, shaken, and the resulting tiny pieces of precious metal recovered) and other practices reduced the weight of gold coins so far that their stated values were of limited usefulness.  Since different locales had different weight standards for gold coins, local metalsmiths played an important role in regulating coins to appropriate standards.

“Regulators” used gold plugs stamped with a metalsmith’s mark to bring underweight coins into line with local weight standards. Burger’s mark consisted of a round or oval cartouche, into which his initials were engraved. The example we will offer in March was struck at the Rio de Janeiro mint and was plugged and stamped by Burger at some point in his regulating career, which spanned 1784 to 1805. Our cataloger notes that “Regulated gold scholar Ralph Gordon considered this style of plug an assay plug, meant only to assess the fineness of the coin but not to modify the weight.” Whatever the plug’s purpose, it’s an important artifact of a turbulent period in our country’s monetary history.

A range of colonial gold coins bear Burger’s regulation stamp, which was not positively identified until the early 1990s. On this example, the plug with Burger’s mark was stamped over King Joseph I’s eye; it was regulated sometime around 1784, possibly as late as the mid-1790s. After 1795, there was little incentive to continue regulating, as the Mint was able to buy, melt, and re-coin world coins into official United States issues. At some point after Burger regulated this coin, it was clipped down to a lower weight standard in use in the West Indies. It lived quite a life, reflecting the complexities of transatlantic trade in the 18th century.

Our cataloger offers this detailed assessment: “Neatly clipped into the tops of the letters in the obverse legend and flush to the peripheral elements of the arms on the reverse. The edge device is consistent and accompanied by a finely denticulated border added to the reverse. The coin is remarkably attractive, alternating between bright medium gold and warmer golden-orange, with tinges of intermingled olive also discernible. Hints of darker patina are evident at the left obverse and right reverse borders. The 6400 reis host coin, sometimes called a half Joe, shows a uniformly sharp strike and ideal centering. Close inspection with a loupe reveals traces of the 1 underdigit within the loop of the primary digit 2 in the date.”

If you are interested in consigning your United States coins or currency to our March 2023 official auction of the Whitman Coin & Collectibles Spring Expo, call 800-458-4646 or email [email protected].

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