Tiger Eye
Tiger eye is a form of quartz family stone that is both metaphoric and a pseudomorph. It starts life as asbestos or crocidolite and then becomes indurated or soaked with quartz laden fluids, capturing the asbestos in a quartz shell.
The asbestos gives tigers eye its cool effects and the quartz its hardness making it a great choice for jewelry.
Back in the 1870's a carat of tigers was worth half an ounce of gold. Today that number is dirt cheap because we have found large sources of the stone.
Blue tigers eye is called "hawks eye" and is formed at cooler temperatures.
There are several exotic types of tigers eye found throughout the world including Marra Mamba, Pietersite and Tiger Iron.