Clarifications on the color of the silver alloy

[GiulyF]

Hy all,
I'm turning to you on the forum because despite my reading I can't find an online, serious and objective source that can give me information on a question that's gripping me.
Often and willingly the color of silver objects varies, this, I believe, is due to the quantity of binder present. What I'm asking for is therefore a sort of "litmus test" to determine this thing by sight. So, a silver that turns reddish is because there is more copper? and otherwise some artifacts that seem opaque, dull and not shiny, as per image uploaded, does it mean that it is purer silver or with the presence of a different binder? tin, nickel, or zinc?? If anyone can give me some details and exhaustive information it would be really appreciated.

G.

[amena]

A long time ago, in the 18th century, assayers were actually able to define the fineness of silver on sight, by comparing the color of the silver to be tested with that of a piece of silver of known fineness.
It should be noted though that they were professionals who carried out tests all the time.
Furthermore, I don't know if this would still be possible now, after there are alloys with metals not available then.
Best
Amena

[AG2012]

Old silver alloys were more complex in composition with traces of several metals and they must have varied a lot depending on the site of ore melting. That could be the first reason of different color.
The second reason is environment where the item is kept; polluted air, humidity and acidity may produce different patina.
Modern alloys are uniform; I can tell how jewelers make .585 and .750: they simply take pure gold ingots with calculated addition of small balls made of pure electrolytic copper. Practically and theoretically exact proportion of e.g. 75% gold and 25 % copper for 18 K.
Regards

[GiulyF]

Dear Amena and AG2012 good morning and thanks for all the info and and secret pills on the subject. it is always nice and useful to learn.
Therefore wanting to reduce to the bone, without stubbornly wanting to find a solution but slightly changing perspective to my question, COULD a greater quantity of reddish color be due to copper? and on this line of interpretation, what variation would zinc, nickel and tin produce on the object?

it seems to me too often that I have to give vague and generic answers, the humidity and the presence of other metals and the conservation environment... and not effective and conclusive, but I'm not saying they are wrong statements, absolutely, but I would like to be able to say, ok this is more ductile because it is almost pure silver...as if I had to answer a clear question from a child who expects a univocal and crystalline answer
I hope I was clear and not liable to have offended anyone!

[amena]

Well
COULD a greater quantity of reddish color be due to copper?
Answer: Of course yes
what variation would zinc, nickel and tin produce on the object?
answer : I imagine that the alloy would be whiter than if made with copper alone
is this more ductile because it is almost pure silver.?
Answer: Of course yes
HOWEVER
often certain pieces of 800 silver are subjected to a galvanic silvering to make them more brilliant
to see the true color of the alloy you must completely remove all traces of patina
the softness of the alloy also depends on the heat treatment undergone in the manufacturing process.
In other words, there is no simple answer to a complex question

[GiulyF]

[quote=amena post_id=211266 time=1683109660 user_id=20898]
Well
[i]COULD a greater quantity of reddish color be due to copper?[/i]
Answer: Of course yes
[i]what variation would zinc, nickel and tin produce on the object?[/i]
answer : I imagine that the alloy would be whiter than if made with copper alone
[i]is this more ductile because it is almost pure silver.?[/i]
Answer: Of course yes
HOWEVER
often certain pieces of 800 silver are subjected to a galvanic silvering to make them more brilliant
to see the true color of the alloy you must [u]completely[/u] remove all traces of patina
the softness of the alloy also depends on the heat treatment undergone in the manufacturing process.
In other words, there is no simple answer to a complex question
[/quote]

<<In other words, there is no simple answer to a complex question>> you are right, even if sometimes reality surprises us.

thanks Amena

[Truls J Tonsberg]

After some years, I have experience from silversmith production and the sale of antique objects.
The color of the silver item comes 80+% from where it has been stored. Sometimes the silver stays shiny in smoky rooms and sometimes the silver turns yellow/blue in the cleanest room, so hard to say the reason other than it comes from the air. All objects that have a lower quality than 925 s are silver plated with 999% pure silver before sale after production. The color of objects made of 925s+ often has a nice silver/white/black color like the old mirrors produced of silver and glass. Also because there is a little bit of the dark glow skin left = (copper that becomes copper oxide during soldering) In Norway we use 2 alloys 830s=830/silver and 170/1000 copper 925s= 925/silver and 75/1000 copper If you are talking about metal that has come to light due to wear on the silver coating, it is best seen if you polish the object with silver polish and rag and then hold a white A4 sheet next to the object so that you can see yellow fields on the object. The item in the picture needs a polish with a cloth to get the nice silvery color back and away with oxide.

[oel]

All objects that have a lower quality than 925 s are silver plated with 999% pure silver before sale after production.

'
I don't quite agree. For a better understanding some techniques to create a long lasting 'shinning' silver color ;
To burnish;
Burnishing is the application of a high gloss to gold, silver or platinum by means of a burnishing steel or burnishing stone with an agate end.
With the burnishing steel or the burnishing stone, green soap (detergent) is rubbed hard over the surface of the object to be polished. Due to the high-gloss finish of the burnishing steel or the burnishing stone, and the force exerted on the object, in combination with the soft soap, the object's surface is rubbed completely smooth.
If the object has also been frosted/whitened in acid beforehand, it will remain free of tarnish for longer, because the acid dissolves the copper in the precious metal surface skin and in fact a very thin layer of fine silver / fine gold surface is created by frosting. A gold or silver object is created with a thin outer layer of almost pure gold or silver.
Silver processing such as annealing and soldering blacken the surface of the silver object, because the copper present in the silver alloy when heated oxidizes to black copper oxide. The copper oxide dissolves in the acid during whitening, leaving an extremely thin skin of pure silver on the workpiece. This silver skin has a white color and is made high-gloss by burnishing. Also the porous silver skin is pressed closed with a burnishing steel and a completely smooth surface of fine silver is created that retains its shine longer than with polishing, with the result that dirt is less able to settle on it.
Unlike hand polishing and machine polishing, no silver is removed during burnishing. With table silver, burnishing improves hygiene. Although burnishing is less suitable for mass production, silver factories in the past often had large burnishing departments. Burnishing technically requires a completely different skill than machine polishing. Some silversmiths believe that burnishing with old beer gives better results than with soapy water.

Why does silver tarnish
https://www.assayoffice.co.uk/news/ever ... er-tarnish#
To prevent tarnishing 'modern' silver can be rhodium plated or lacquered .
Argentium silver
https://en.wikipedia.org/wiki/Argentium_sterling_silver

Peter.
Source; Het Zilver lexicon Janjaap Luijt