doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com gold inlay question?

I thought maybe someone here could help me with this question .
Im working on a mid 18th century English percussion sxs .
While in the process of re finishing the barrels one of the gold inlay bands on one of the breeches popped . It wasn’t to thick in a couple places to start with .
I had assumed do to the color that it was yellow brass not gold .
However when I replaced the band with yellow brass it did not match at all after polishing .
So I took the piece that popped out down to a metal buyer and had them test it .
According to them it was 18-20 KG .
So I replaced the band with 18 KG
It matches better but still a couple shades off .

So here is my question .
Could the issue be that some other type of metal was mixed with the cold 150 years ago to make 18 KG ?
I have replaced these inlays on other SXS and had brass match very well but this one it did not . Was there another type of material used to substitute gold on lower grade barrels and has the gold alloy changed through the years ?

The gold % of the alloy content hasn't changed any. The number still indicates the % of pure (24k) gold that the alloy contains. 18k is 18/24 pure gold,,,,20k is 20/24 pure,,,14 is 14/24 pure,,etc.
The remainder can be any number of different metals of combinations of them. Some purposely alloyed to bring out a different color shade to produce for example green and rose golds (both 14k alloys IIRC).
A gun that early may very well have had the gold inlay done with an alloy that was just the result of the engravers recyling the tiny scraps and filing from the bench. A couple of different 'k' alloys to start with plus a few tiny unwanted bits of brass, copper, perhaps nickle mixed in and a quite different alloy appears each time it is done.
Now we buy gold in pure and alloy designations and it is right on the money as far as content. Matching the older stuff can be a problem because much of it was not..

thank you Kutter . i suspected this but frankly did not think about it tell after the fact
while i understand the % of pure gold has not changed , the mix or remainder was what i was getting at . any variance between the actual alloy make up would change the color .
again thank you for your reply

There is often a subtle color variation in different purities of gold; as a dentist, one often can judge the 'type' of gold utilized by the color. This doesn't even take into consideration anything else added to alter coloration or any other properties.

Rick

Post this on the Engraver's Cafe, I don't have an address but you can find it. They will know.

i been speaking of this over on the Lindsay site .
dont go to EC that much prefuring Steve lindsays forum .
but thank you for the input

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