Prata Wolff

[AMustela]

This seems to be a bit unusual, but I know the mark/maker. What I don't know is what the item is made of or anything at all about the maker.

I have a Prata Wolff covered serving dish but the only mark on it is the W and Prata Wolff. I assume that is silver plate however there are no stamps of any kind other than the makers mark and name. I have looked extensively on the Internet and silver forums and can only find a minute amount of information on the maker and where it's from (Brazil) and what I could find was only a post or two about flatware and the 90 mark. Some say it means 90% silver, some say it doesn't. Some say if it has no mark, it's 90% silver and if it has a mark it's silver plate. So confusing. Can anyone enlighten me on this topic or direct me to where I might find accurate info? I've learned that they make some things out of stainless steel as well, however this dish has tarnish on it, so I don't believe it's stainless. Thank you.

[AG2012]

Hi,
There are exactly the same items made of silver (prata) and stainless steel.
The link to their catalogue:
https://www.wolffbrasil.com.br/catalogo

Marks are not shown, though.It goes without saying that stainless steel is magnetic, silver is not.
So, test it with magnet then electronically for the exact composition.
I would be tempted to acid test it with deep filing but that is not good although I sometimes did it and polish where filed.After all, it is not old silver, not much harm done if that is the only way to prove you have solid silver.
Regarda

[amena]

Some types of stainless steels are magnetic, other types are not. The magnet test is not conclusive.
In any case, as far as I understood, the products are made of stainless steel AND silver (i.e. silverplate), not stainless steel OR silver.
Regards
Amena

[AG2012]

Hi,
Magnetic test is done to exclude, not to prove.
If positive it excludes silver.
If negative.it does not prove it IS silver.
In short, magnetic test is done to EXCLUDE precious metals (if positive). Although platinum is very weakly magnetic.
Never heard of non magnetic ferro alloys and steel.
Regards

[amena]

There are several families of stainless steels with different physical properties. The magnetic properties of stainless steel are very dependent on the elements added into the alloy. A basic stainless steel has a ‘ferritic’ structure and is magnetic, formed from the addition of chromium – it can be hardened through the addition of carbon, making it ‘martensitic’. However, the most common stainless steels are ‘austenitic’ – these have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it theoretically non-magnetic.
304 stainless steel contains chromium (min. 18%), and nickel (min. 8%). It is an austenite steel and is only slightly responsive to magnetic fields. It also contains 18 – 20% chromium and 8-10.50% nickel, and lesser quantities of some other elements.
316 stainless steel is a molybdenum-alloyed steel. The fact that it is also negligibly responsive to magnetic fields means that it can be used in applications where a non-magnetic metal is required. It also contains a number of other elements in varying concentrations.
https://www.greenwoodmagnetics.com/reso ... ess-steel/