The chip is uniface (as are all pieces in the set),
and part of an 11-denomination set which originally
came from Portugal and ending up in South America -
making it's way to Dania, Florida. The monetary unit
sign you see after the denomination was incorporated
inte an old unit Portugal used many, many years ago
(R/s). The six or seven pieces now being offerd at
eBay are the smallest in the set. They range from
3/4" to 1-1/4" while the larger pieces are as big as
4" oval and gold bar shaped. I valued the complete
set for the owner at $60,000+ a couple of years ago.
I've also sold some of the smaller pieces at eBay
during the last few months to pearl collectors.
JB