Agate is the name given to a huge variety of Chalcedony, it is formed
from microscopic crystals of quartz laid down in bands. It comes in
many different natural colours and is a common stone native to USA,
India, Brazil, Africa and Botswana to name a few. I myself tend to use
Moss, Red and Indian Agates as these are my favorites but have used
many others. I haven't looked too far into it's healing and spiritual
properties but Agate is a good grounding stone, soothing and calming
and just what I need concentration! It has so many other attributes as
with all natural stones, I would certainly recommend you looking into
them further.