Weight Loss on Shipwreck Coins

koincollect

I was looking at some silver shipwreck coins, mostly 8 Reales and see they they have a loss of about 25-30% of their original weight and in one particular case about 50% and still retain almost all of their design. Does anyone know how is this possible? I usually keep away from these but bought some cool coin clumps from Daniel Sedwick.

coinpro76

Dang I thought this was a new miracle diet

Silver does react with other chemicals, causing it to oxidize or degrade on a molecular level. Silver kept in salty seawater is fairly good conditions for some reactions over time. I believe (dont quote me please) silver can react in a way that it will break down, separate or fuse together, Kind of like Iron would but way less extreme and not in a rusting way but similar idea with oxidization.

If anyone can further break it down or correct me please do

jgenn

The corrosive effect of seawater causes the loss of metal from both fields and details, probably at the same or closely similar rate. This is different from the loss of metal from circulation, which affects the high points first.