A gemstone is a precious or semi-precious stone, especially one cut, polished, and used in a piece of jewellery.
Gemstones can be the following:
There's many more gemstones that exist in the world than just these twelve, but you get the general idea.There are 2 birthstone of august month: Peridot and Sardonyx.
Easy one for me. My lady was born on the 30th and the birthstone is called Peridot. Beautiful green gemstone. The are actually two but Peridot is the main one. The other is called Sardonyx.