Whats the most expensive gemstone in the world?
Emerald, by its weight, is the most valuable and thus expensive gemstone in the world. However, it is much harder to find an emerald without noticeable inclusions than a diamond, so when shopping for stones, diamonds will often be more expensive. Emerald is one of the five precious stones, which are usually the most expensive: diamond, emerald, ruby, sapphire, and amethyst.
