Agate was named by Theophrastus, a Greek philosopher who also discovered the stone sometime between the 4th and 3rd centuries BCE.
It mostly made up of Chalcedony and Quartz.
There have been deposits of this stone found all over the world including Brazil, Mexico., the United States and Poland.
It is characterised by it's banded pattern and is found in a range of colours including grey, red, brown, yellow, orange and white.