Several types of hallmarks can be affixed to jewelry:

• the diamond-shaped maker's mark, which authenticates the creator and origin of the jewelry
• the “925” hallmark, which designates jewelry made in 925 silver
• the guarantee hallmark: a head of the neck brace which must be
obligatorily marked on silver jewelry weighing more than 30 grams.
This hallmark is stamped by customs

• for jewelry containing silver and anodized aluminum, the letters “AL” are engraved on the jewelry.