Stunning Varieties and How They Are Formed By Bob Lynch and Dan R. Lynch The authors know agates, and this definitive book on the agates of Lake Superior was 30 years in the making! Each type of the regionÆs agates is discussed in-depth, with details ranging from characteristics and formation to distribution and rarity. Multiple photographs accompany each write-up. YouÆll likely find everything youÆve ever wanted to know about Lake Superior agates within the pages of this book! 224 pages | 8-1/2" x 11" | softcover