Real butter. Eighteen karat holds more gold than the alloy most chains are made from, and the colour is deeper and warmer for it.

We bought her for that colour. It is the one thing a lower karat cannot copy, however well the chain is made. High-karat gold is soft, so at 1.0mm she moves and settles rather than holding a shape. At 18" she clears a collar and sits just under the notch of the throat, which is the length most people land on when they only want to own one.