Michael Gienger (1964-2014) was one of Europe's most respected experts on crystals and their uses, a field in which he had been active since 1988. He started collecting minerals in 1972, and in 1985 a successful self-treatment with healing crystals inspired him to pursue further training as an alternative healing practitioner. He was trained in shiatsu and completed a two-year apprentice in shamanic healing. He went on to author more than 20 publications, a number of which have become standard works in their field and have been translated into 11 languages.