Shipwreck effect on weight of coin

zski123

Good afternoon,

I am looking at a 1733 8 Reales Mexico which was supposedly taken from the Rooswijk shipwreck and excavated approximately 200 years later. The coin looks to have the earmarks of 200 years of seawater but wondering how much impact there should be on the weight of the coin. In this case, the weight is 24.9 grams. The wear looks reasonable but wondering if the exposure to the sea would knock 2.4 grams from the weight? Thanks for you input.

CIVITAS

Easily, depending on how severe. Some Atocha pieces are 30-40% underweight or more.

zski123

Wow! That's really interesting. Thank you.