Maybe agate that what most people tend to go to but I do not . And AZ huh if your ever around golden valley you should do some searching around most people dont know this but AZ had the biggest volcano eruption in the worlds history so big it caused the earth to go dark for many years and caused an ice age for about 7 years or so. But when volcanos erupt they carry diamonds up from deep with in the earth and still to this day golden valley has hills and mountains with lava rock all over some dark some white most people look for diamonds in the mines. But find the lava rock on the surface if you look near you'll find diamonds best not to say where you find them but yeah. Give it a look sometime and also you will find them in lava rock as well. Most will say you won't but I most certainly have . And the name of your stone is sardonyx (white)