When experts evaluate what can be considered extraordinary jewellery, they take a look at quite a few factors. One of the main factors they look at is the gemstone set into the piece. The cut, rarity and size of the gemstone can make a piece standout. For example, we look carefully at the diamonds set into our antique diamond rings. The metalwork features of the piece can also make a piece of jewellery extraordinary, as well as the scarcity.