We have some great rocks in Oregon. If you ever want to go out rock hunting, this is the book to bring! We have almost every rock hunting book for every state in the country, too.
Gem Silica with Azurite and Malachite. Gem Silica or Gem Chrysocolla is a rare form of chalcedony colored by copper ... It is often found mixed with malachite, azurite, turquoise or quartz.