Sure enough, OK to quote me a little. For a wee bit of history, a pair of silver reales of Charles and Johanna of Mexico, much like this coin, were unearthed in a Native American burial mound along Spruce Creek, a tributary of the Halifax River in Eastern Florida back in the winter of 1871. Identified as a funerary deposit (circa 1550s), one of the coins was still resting in the eye socket of a skull, deemed a "Charon's Obol" after the ancient practice of paying the shadowy boatman to cross the River Styx. This find was reported in correspondence from "S.C.C" of Jamaica Plain, Massachusetts, "Opening of a Burial Mound in Florida," from the American Journal of Numismatics, (AJN) Vol 6, #1 of July 1871, page 16. The theory is that numerous Spanish ships were wrecked on the coast of the Spanish colony of La Florida, in the 16th century with some coins from those wrecks salvaged by the Native Americans who wore gold and silver ornaments. See "Numismatic Finds of the Americas" by John M. Kleeberg, Numismatic Notes and Monographs #169 of the
American Numismatic Society. I'm not sure if this information will help or hurt your sale, so use your own judgment.