Genesis and Classification of Agates and Jaspers: a New Theory by Marco Campos-Venuti
A signed copy of Marco Campos-Venuti reference book. He is a PhD volcanologist and editor of the Rivista Gemmologica Italiana. He is a passionate collector of stones and has a curiosity that led him to investigate their origin. He has an important collection of agates and jaspers and has written many scientific papers.
This book shows a new geological model that explains the formation of most of the microcrystalline and amorphous varieties of silica. The most important conclusion is that silica varieties take their origin in a meteoric environment with a strong influence due to the weather and alternation of wet and dry seasons. The book is filled with beautiful photographs that illustrate the principles and capture the attention of the reader.