Brucite nemalite

A formal description of a mineral presents all the physical and chemical properties of the species. In particular, distinctive attributes that might facilitate identification are noted, and usually a chemical analysis of the first or type specimen on which the name was originally bestowed is included. As an example, the complete description of the mineral brucite (Mg(OH)2), as it appears in Dana s System of Mineralogy, is presented as Appendix 3. Note the complexity of this chemically simple species and the range of information available. In the section on Habit (meaning shape or morphology) both acicular and fibrous forms are noted. The fibrous variety, which has the same composition as brucite, is commonly encountered (see Fig. I.ID) and is known by a separate name, nemalite. ... 

Fibrous. Nemalite Nuttall (Am. J. Sc., 4, 18, 1821). In fibers or laths, usually elongated [1010] but sometimes [1120]. Some fibrous brucite is reported to be highly ferroan, but this may be owing to admixed magnetite. 

Kogure T, Bunno M (1998) Microstracture of nemalite, fibrous iron-bearing brucite. Mineral J 20 127-133 Kogure T, Murakami T (1996) Direct identification of biotite/vermicuhte layers in hydrobiotite using high-resolution TEM. Mineral J 18 131-137... 

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