Agate is a hard stone,within the range of 7-9 on the Mohs scale. Agates are found in all colors of the
rainbow. Agate is a type of chalcedony. It's formed from layers of quartz. That is how it has varicolored bands. It occurs usually as veins or nodules. There are a variety of unusual banded and scenic markings.
Tiny quartz crystals from within the stone thus adding to the beauty of the stone. These crystals are called drusy. Thes drusys are often cut from the agate as used as cabochons or a stone itself.
There are a variety of agates; moss agate, plume agate, eye agate, lacy agate, banded agate, brecciated agate, botswana agate, fire agate, crazy lace agate, moss agate, rainbow aggate, picture agate,tree agate and many more. Agate is found all over the world; Asia, Africa, Brazil, Italy, Germany, Nepal, Mexico and USA.
Polymer clay is so versatile and has the ability to be made to look like real stones too. These are faux agates made from polymer clay faux agate beads I have yet to use them in a design. I think i will be using some copper findings; it will highlight the stone.
To read more about agates http://en.wikipedia.org/wiki/Agate
Some beautiful pictures of agates http://www.agatenodule.com/index.htm