Author Description

The present volume is the first of a series describing Mn minerals. There has been no attempt to provide a thorough (bibliographically complete) coverage of the literature. Rather, a selection of papers was undertaken to cover especially the various aspects of occurrence and genesis. Papers that only mention an occurrence of a minerat species without additional data will not be taken into account, except if they represent an unusual type of occurrence. The volume starts with a brief outline of the chemical and geo-/cosmochemical character istics of Mn; its abundance and distribution in the cosmos and on earth; and its distribution in minerals. The main part describes the native metal, its solid solutions with Fe or Al, and silicides and carbide; the sulfides and related compounds; the halogenides and oxyhalogenides; and the oxides of type MO. The minerat descriptions comprise the following topics: occurrence (comprising data on paragenesis, intergrowths, inclusions, and alteration); chemistry (comprising complete analysis, formula, diadochy, and the relationship be tween composition and type of geological occurrence or composition and physical proper lies); crystal form and structure; optical and other physical properties; and chemical and thermal behavior. Frankfurt am Main Wolfgang Töpper April 1993 Table of Contents Page 1 Natural Occurrence, Minerals . . . . . . . . . . . . . . . . . . .