#1...Mucho Kudos on the sharp, focused, well lit photos ... your photos give us a lot of info ...see attached diagram ...
...Definitely from the Lima, Peru colonial mint, as indicated on the design: the "waves" dip down in the middle, below the date (a feature that was exclusive to the Lima mint) ...
...visible on this cob's "Pillars & Waves" side is all the info we need ... you have the mint mark "L" (Lima) visible, the denomination "4" (reales) visible, & the mint assayer's mark/initial "H" visible ... visible in the center of the design is (most of) the Latin motto: PLVSVLTRA (plus ultra/"more beyond" ... the letter "V" is used in place of "U" in Latin...) ... on the bottom row, center, you can barely make out the 3-digit date "7 0 4" (for 1704 ... last three digits only were used to represent the date on this era's coinage at the Lima, & other colonial mints) ...
...correct silver purity for this cob was set at .931 pure, but the salt exposure has most likely leached some copper from the coin, thus, making the purity a bit higher ... correct weight for a 1704 Lima 4 reales was set @ 13.73 grams, but this coin is likely under that weight due to corrosion ...
...MAN! ... that's a cool find! ... I had assumed that you were on Florida's "treasure coast", but as
sandog pointed out, looks more like another location ... I'd be scouring that area ...
...I've included a pic of another 4 reales, same date, for comparison ...
...p.s. ... anyone interested: search "cob Pillars & Waves design", & learn the significance, so you'll know what you're looking at next time the opportunity rolls around...
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