Weight Loss, Detail Loss, and Authentication for Shipwreck Coins
airplanenut
Posts: 21,908 ✭✭✭✭✭
These three 8 Reales came in and I'm working to authenticate them. All three have corrosion or other detail loss consistent with shipwreck-salvaged coins, and all three are also underweight (unlike most problems, I can imagine a century or two in salt water can eat away a few grams of metal). Any thoughts on whether these coins are just damaged or if they may have authenticity issues? I don't have any paperwork to tie them to a specific wreck, though I've seen a fair number of of El Cazador coins dated 1783-Mo FF, so that could be a decent guess.
1: 25.3g
2: 24.5g and heavily polished
3: 23.3g... while the other two coins ring like silver, this one is a bit tinnier--it's not the thud of lead, but it's not the full ring of silver. If corrosion doesn't change the composition of the remaining metal, I'm not sure I can explain how just losing some metal would appreciably change how the coin rings.
Your thoughts are appreciated! I'll also note that these coins are unrelated (different source) to the chopmarked 1747 8R I posted separately, so while I have the same overarching question (authenticity) for all the coins, that I have all of them right now is a coincidence.
Comments
On the one hand, they look just like thousands of other 1783's off the El Cazador wreck, so I have little doubt that they're real. On the other hand, when a coin is that far gone, it's difficult to be 100% sure. Anyway, I'd be very comfortable buying or selling these particular coins.
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
8 reales are difficult to authenticate without environmental damage. With this kind of damage they are impossible to authenticate. If you care about only dealing in authentic items, then your best bet for shipwreck coins is a certificate of authenticity from a reputable salvage company or their conservation service.
Shipwreck coins have the tendency to become finer silver actually, as the other metals can get leeched out of them over time. That could account for the difference in ring.
Gobrecht's Engraved Mature Head Large Cent Model
https://www.instagram.com/rexrarities/?hl=en
The "ring" of a coin depends as much on its shape as its composition. If you make a coin thinner (by corroding it evenly on all sides), that will certainly alter the pitch of the ring.
Roman emperor Marcus Aurelius, "Meditations"
Apparently I have been awarded one DPOTD.
These shipwreck coins look fantastic. The history behind them if know would have to be truly amazing.
USN & USAF retired 1971-1993
Successful Transactions with more than 100 Members
Are there any clues in the edge designs? Maybe the opposing overlaps are present? Peace Roy
BST: endeavor1967, synchr, kliao, Outhaul, Donttellthewife, U1Chicago, ajaan, mCarney1173, SurfinHi, MWallace, Sandman70gt, mustanggt, Pittstate03, Lazybones, Walkerguy21D, coinandcurrency242 , thebigeng, Collectorcoins, JimTyler, USMarine6, Elkevvo, Coll3ctor, Yorkshireman, CUKevin, ranshdow, CoinHunter4, bennybravo, Centsearcher, braddick, Windycity, ZoidMeister, mirabela, JJM, RichURich, Bullsitter, jmski52, LukeMarshall
In this case, the history is known and it is amazing. Google “El Cazador shipwreck”.
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.