Ramsdellite synthetic

Ramsdellite is thermodynamically unstable toward a transformation into the stable ft -modification. Hence, it is rarely found in natural deposits. Natural ramsdellite has a stoichiometry close to the composition of Mn02 and can be considered another true modification of manganese dioxide. Attempts to synthesize ramsdellite in the laboratory usually lead to materials of questionable composition and structural classification. It is very likely that synthetic ramsdellite materials are more or less well-crystallized samples of the y-modification that will be described in more detail below. 

Chemists often place a, /3, y and so on as prefixes before chemical compositions for simple synthetic ones which occur in many forms, whether natural or not [e.g. a-Fe203,, y-Mn02 ] these are not mineral names because they are not made up of words but of chemical element symbols. If they do occur in nature, they will also have a name in words (i.e., hematite and ramsdellite respectively for the given examples). 

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