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ferromagnesian

American  
[fer-oh-mag-nee-zhuhn, -shuhn] / ˌfɛr oʊ mægˈni ʒən, -ʃən /

adjective

Mineralogy.
  1. (of minerals and rocks) containing iron and magnesium.


ferromagnesian British  
/ ˌfɛrəʊmæɡˈniːʒən /

adjective

  1. (of minerals such as biotite) containing a high proportion of iron and magnesium

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ferromagnesian Scientific  
/ fĕr′ō-măg-nēzhən /
  1. Containing iron and magnesium. Magnetite and hornblende are ferromagnesian minerals.


Etymology

Origin of ferromagnesian

First recorded in 1900–05; ferro- + magnesi(um) ( def. ) + -an ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Thus magnetite, apatite and picotite, with olivine, may be enclosed in augite, hornblende, and hypersthene, sometimes with a later growth of biotite, while the felspars occupy the interspaces between the clusters of ferromagnesian minerals.

From Project Gutenberg

A fluxion structure or flow banding also can be observed in some of the rocks of this series, and is characterized by the occurrence of parallel sinuous bands of dark colour, rich in ferromagnesian minerals, and of lighter shades in which felspars predominate.

From Project Gutenberg

Biotite and all ferromagnesian minerals rarely appear in them, and never are in considerable amount.

From Project Gutenberg

The ferromagnesian minerals crystallize comparatively early and have some idiomorphism; the felspar usually follows and only in part shows good crystalline outlines.

From Project Gutenberg

As they are richer in the dark coloured ferromagnesian minerals they are usually grey or dark grey, and have a higher specific gravity than granite.

From Project Gutenberg