I've been back there once and found a current dime and 2 pennies. As for cleaning them, I tried the Olive Oil for a couple of days (didn't seem to loosen anything) so I wraped them in individual foil strips (make sure the foil is not crinkled at all) put them in seperate bowls covered with vinegar for 24 hours then after pulling the foil off I alternated between Tarnex and a cornstarch/water paste to rub them clean. That actually took over an hour. As for the year of the coin I kept searching the internet and found an identical coin, this is what was said about that coin and that coins picture: 1 R Mexico Assayer O Philip II cob Mo-O between 1572-1598
Obverse: [PHILIPP]VS . II . DEI GRATIA
Reverse: [HISPANIARVM] . ET : INDIARVM [REX]
Weight: 44.5 g (2.88 grams) Diameter: 22.7 mm
Comments: This coin has been heavily clipped and is well below the authorized weight of 3.38 grams. Most of the upper
potion of the legend letters has been clipped and in parts the entire legend is missing. According to Pradeau (p. 42) there
should be colons between each word. Although this coin is clipped it is better than the plated coin in Pradeau (plate 2, item 5).
Obverse bears the crowned Hapsburg shield, to the feft is the mintmark 'Mo' for Mexico City, while to the right is the
assayer's initial 'O'. According to Pellicer i Bru's, Glosario, p. 161 this unidentified assayer O was active during the entire
reign of Philip II 1556-1598. As this coin is a Mexican cob it cannot date to before 1572 when the dies used on the cobs
first arrived in the New World. The reverse bears a cross with fleur-de-lis transformed into balls at the ends, which is unique
to the Mexico City mint. The Castile and Leon arms are completed with castles in the upper-left and lower-right quadrants
and lions in the upper-right and lower-left quadrants all surrounded in what in heraldic termonology is called a tressure
(here represented by a border consisting of four arcs and four pointed sections).
Provenance: From the Robert H. Gore, Jr. Numismatic Collection.
After further research I have concluded the coin had been from the San Martin, almiranta of the Honduras Fleet which sunk in 1618. I tell ya....finding this coin was....whew, exhilarating to say the least! But the research brought a whole different detph of meaning to me where this coin is concerned. Thank-you for letting me share this wonderful experience with you! Tammy