Lobster Clasp
A spring-loaded hook shaped like a lobster claw. The most secure everyday clasp and the modern default.
A lever compresses a spring to open a gate, which snaps shut when released. Nothing passive can open it.
The spring is the weak point. After years of use it weakens, and the gate stops closing fully.
Size should be proportionate to the piece. An undersized lobster clasp on a heavy necklace is a break waiting to happen.
When you are buying
Check the gate closes flush with an audible click. Any visible gap means the spring is already tired, even on a new piece.
Clasp
The fastening that closes a necklace or bracelet. The most common point of failure and the most overlooked part of a purchase.
Screw Clasp
Two halves that screw together, usually shaped as a small ball. Traditional on Indian pearl necklaces and very secure.
Box Clasp
A folded metal tongue that clicks into a box. The traditional fine-jewellery clasp, usually with a safety catch.