I have absolutely no idea how we came to own this book. It is mostly a photobook, featuring turquoise from different mines around the world and what local artisans have done with the stone. Besides telling the history of each mine and how to tell the stones from each mine apart, there's valuble information on different jewelers' styles (say traditional Navajo vs. Zuni carvings) and how to tell imitation and treated and natural turquoises apart. It's an excellent resource for jewelers or stone collectors. ( )