Jewellery is articles of personal adornment, like rings, necklaces, bracelets, cuff links, and pins. Jewellery is made from metals (especially gold and silver), stones, glass, plastic, and other materials.
In UK English it is spelled ‘jewellery’ while in US English it is spelled “jewelry”.
A jump ring is a circular metal ring with an opening. It is used to attach two other rings or links, and is then soldered or pressed shut.