The www.gleeson.com site a link to http://www.bcvc.net/faro/ which in turn had all the rules.
From the www.bcvc.net/faro site:

COPPERING: From 1853 on, punters (players) had the option of "coppering" their faro bet(s). This means placing a copper token (traditionally a penny or later a 6-sided composite token, called a "copper") on top of a standard (often called an "open bet" or "straight bet") wager to "reverse" the bet. What this means is, a "coppered" bet wins on the first (losing) card, and loses on the second (winning) card, the opposite of a regular bet, whether it be on a particular card, a pair or group of cards or the "high card" bar. The 6-sided "coppers" are approx. 1" in diameter.

Thanks for the lead!!