The design of the item is copyrighted, meaning you can't manufacture a product that looks like the original (a knock-off), or is so similar it's obviously derived from the original. The silverplate is pretty much irrelevant, unless it is a unique factor of the design, which is unlikely.
Silver plating processes were once patented, not copyrighted. Some techniques may still be patented, but you wouldn't be able to tell one from another by looking at the product.
Gold plated over silver means that the ring is made of silver with a thin layer of gold plated to it. It is not solid gold but solid silver with gold on it.
It means the object is plated with pure silver.
It stands for silver plated which means that the piece of jewelry is covered in a thin layer of silver.
I believe it means double plated silver. Xxx means triple plated.
EPNS stands for electro plated nickel silver. This means that it was made after 1900 and is of no interest to antique collectors. The value is about $20 if you can find a buyer. There are not many buyers for silver plated items.
The HPNS marking means "Heavy Plated Nickel Silver". this means it is silver plated only - not sterling or coin silver composition.Visit the link below to learn more about various silver markings and gold markings.
It means the object is plated with pure silver.
SP means a ring is silver plated
I think it means silver plated
Electro-plated nickel silver
it means its silver plated - made by Walker & Hall Ltd
866 means silver plated sorry