What Is It?? Fire Agate

Another entry in my series (yes, it's a series now) of 'What Is It?'.  This time, Fire Agate.  True fire agate is quite rare and found in Arizona mostly, plus spots in California, New Mexico and Mexico.  It is an iridescent agate, the 'fire' cause by inclusions of other materials.  It is not crackled glass from China.  The following pictures are a fair piece of my own stash.  I rarely work with fire agate, because like opals, you can cut right thru the fire in half a second, leaving yourself a nice brown rock . . .