Brasher Doubloon denomination is listed as $15... why?

It was a special treat to see the Brasher doubloon with EB breast punch at the recent Sacramento ANA show. (I've stolen Rick Show's photo from Charmy's show report to post here). But I'm wondering why PCGS lists the denomination as $15. Is it simply because of bullion weight?

When in doubt, don't.
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www.brunkauctions.com
The coin is called a Doubloon because it is approximately equal in weight to the Spanish Doubloon which circulated actively in colonial America. A value of $16 was initially attributed to the coin, but later research shows that this value was erroneously placed and the “Doubloon” was actually worth $15 at the time of issue. This value was first suggested in a comprehensive article about Brasher Doubloons written by numismatist William Swoger and published in the June 1, 1992 issue of Coin World magazine. Additional information about weights and measures of the era was published in the 1993 book, "Money of the American Colonies and Confederation," by Phil Mossman.
David McCarthy, numismatic researcher for The Brasher Bulletin, the newsletter of the Society for Private and Pioneer Numismatics agrees. "The coinage standards of weight and value established by the Bank of New York in 1784 indicate that Doubloons weighing 17 pennyweights (about ¾ of an ounce) were valued at $15. Brasher's Doubloons weigh 17 pennyweights, and would therefore have been $15 coins," said McCarthy.
Coin's for sale/trade.
Tom Pilitowski
US Rare Coin Investments
800-624-1870
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