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Monday, November 23, 2020

11/23/20 Report - Recently Found Ring. Gold, Ancient Gold, Depletion Gilding: Encrustation and Discoloring.

 

Written by the TreasureGuide for the exclusive use of the Treasure Beaches Report.

Ring Found Friday by Terry S.
Photo by Terry Shannon.



Yesterday I showed some recent finds made by Terry S. including musket balls and a reale found.  Terry S.  also sent me a photo of another item he found Friday. It is the ring above.

Here is what he said.

I found this ring Friday and I believe it’s a low karat gold and could date back to the ship wreck era. This ring is very heavy and the readings on the detector indicate it’s gold, It reads a steady 13 on the Equinox. I had it in the tumbler for a while and under a light you can see what appears to be gold . I quit messing with it and have contacted a couple experts for their opinion and if it turns out to be something good I’m going to arrange to have it cleaned by a professional. I did hit it with my scoop during recovery and did some damage and that sure sucks...

Terry wanted opinions about the ring.  Let me know what you think.

I think you can see the floral design on the ring.  

I didn't post this find the same time as Terry's other finds because I was planning on doing some posts on how items can be encrusted or discolored over time on a beach or in the water.

The photo above shows very little of a gold color, but we only have an image to look at.  We can't see it as Terry does.

You've probably heard that very much unlike silver, gold comes up looking bright  and shiny even if it has been on  the ocean floor for centuries.  That is often true, but gold can get encrusted or discolored.

Below are two 14K rings that were found Saturday.  I posted a quick photo of them Saturday showing how they looked when found.   Here are the two rings as found.

Two Encrusted Gold Rings Found Saturday.


Notice that both rings are encrusted, but the one on the right is most heavily encrusted.  

I know that isn't a great photo, so here is a closeup of the one on the left.


Encrusted Ring.


You can barely see the outer surface of that ring because of the encrustation.  And remember, it is not as encrusted as the other one, which I did not photograph before cleaning.

After a few hours in white vinegar, here are the two cleaned rings.  They are both marked 14K.


Encrusted Gold Rings Partially Cleaned. 


The bottom ring in this photo is the encrusted ring shown above.  Most of the surface is now visible, but some of the encrustation remains - mostly in the crevices.  

The top ring was more heavily encrusted before digging, but is now almost totally clean.  My main point here is that even gold can become encrusted, and it doesn't take centuries.

But here is another example.  This gold Christ figure was found at John Brooks many years ago.  


Closeup View Christ Figure Found Years Ago On A Treasure Coast Beach.

It looks very much like it did when it was found.  A person might see all that black and think the item is plated and that some of the plating wore off.   However, when examined using sufficient magnification, it is apparent that the black is not the underlying metal.  Under magnification it can be clearly seen that the black is a layer of encrustation on top of the gold.   I suspect that the black can be easily removed.

I've heard people say that if an item is plated it is modern because gold or silver plating is a modern process.  Electroplating was invented in 1805, but the ancients did a lot of plating or layering.  

Notice that it is the high spots on the Christ figure that show as gold, while the black remains in the areas that are more protected where it would not be easily worn off.

I have also shown in the past a 1715 Fleet a copper alloy medallion that was originally plated.  In that case the plating remained on the low more protected areas but was worn off of the high spots. 

On the gold object with a crust, the crust wore off the high spots, but on the layered or plated object the layering wore off the high spots and remained in the low spots.  

Before I go any farther, here is a link to an article on depletion gilding, an ancient process used in Pre-Columbian America to enrich the surface of objects made of tumbaga.


So does Terry's ring look like gold?  Most would say no, but we can't see much of the color of gold that Terry evidently can see much better than those looking at a photo.  The photo shows just a little of that.

And I've shown that gold can be encrusted or discolored, and we know it can be layered, and it can be alloyed, however it is my understanding that even tumbaga would typically be eight karat or higher, which at that lower figure would still be close to what we find in lower carat modern jewelry.

We didn't have access to XRF testing when some of these objects were found, but we do now.  I highly recommend that finds of questionable metallic content be tested by XRF analysis, which will provide a definite detailed readout of the metal or metals involved.  Some pawn shops or jewelry stores will test items for you.  In my opinion that is the best way to resolve such issues.

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Let me know what you think of Terry's ring find.

Today the surf will be something like 3 - 5 feet.  The tides won't be big,  We are supposed to have some north wind.  I'll be watching to see how that turns out.

Happy hunting,
TreasureGuide@comcast.net