Used jewelry can be classified according to its age and style
Antique jewelry is jewelry that is at least a hundred years old.
Vintage jewelry, on the other hand, is made at least 20 years ago.
Second-hand jewelry is always jewelry that is resold, meaning it has been bought new once and sold/passed on. A similar product may still be available new in stores, a second-hand product can be either used or unused. It is safer to call a product second-hand than Vintage or Antique if there is no information/certainty about the age of the product.
Year stamps of FINLAND's
silver and gold products (letter+number=year)!

SWEDEN, Swedish year marks

Stamps
It is possible to find out about the stamps, e.g. country of manufacture, locality, type of precious metal and its concentration, age and also the designer.
Part of the finesse of old objects/jewelry can be found precisely of this, objects have been valued from the very beginning. They are designed with care, often partially or completely handmade, and with decent stamps, a mark is also left on the next generations...
In foreign, as well as in newer Finnish productions, unfortunately, this information is often minimal. So it is not always possible to find out anything else from the markings other than the material and its content.
Bronze is a metal alloy whose main component is copper. Most commonly, bronze refers to an alloy of copper and tin, but the name is also used for other alloys of copper, except for the alloy of copper and zinc, which is called brass.
Bronze is therefore not a precious metal, so it does not need to be stamped either.You can find the manufacturer's or designer's stamp on the jewelry. The country of manufacture can also appear. For example, Finnish size manufacturers use the (made in Finland) stamp on some of their jewelry. The material marked Bronze is more common in foreign jewelry. However, it should be noted that there are often no stamps, and the color tone can vary a lot.

In Finland, ring sizes are often indicated by diameter, in millimeters. The size can also be indicated by circumference, as in the table above.
The size can also be indicated by +/-
EXAMPLE: size 18+ (18.25mm) or 18- (17.75mm) etc.