Garnierite

Garnierite

Garnierite is a general name for a green nickel ore which is found in pockets and veins within weathered and serpentinized ultramafic rocks. The name was given by Jules Garnier who first described it 1864 for an occurrence in New Caledonia. It forms by lateritic weathering of ultramafic rocks and occurs in many nickel laterite deposits in the world.

Garnierite is not a single mineral but a mixture of the Ni-Mg-hydrosilicates serpentine, talc, sepiolite, chlorite and smectite. These minerals occur in garnierite ores individually and in intimate mixtures.

A detailed study of the garnierite ores from Falcondo Mine in the Loma Caribe serpentinized peridotites of the Dominican Republic showed that the garnierites have compositions within the three series:^[1]

• Ni-bearing talc - willemseite (up to 25 wt% Ni)
• Ni-lizardite - népouite (up to 34 wt% Ni)
• Ni-sepiolite - falcondoite (up to 24 wt% Ni)

The lateritization of ultramafic rocks gives rise to a strong dissolution and removal of magnesium and silicium which leads to a strong residual concentration of iron and nickel in a goethite-rich surface layer (nickel limonite ore). A portion of the nickel is leached downwards and finally fixed in the underlying decomposed ultramafic rock. This process gives rise on the one hand to a moderate nickel increase of the total decomposed rock (nickel silicate, nickel saprolite); on the other hand relatively small amounts of nickel-rich garnierite ore are precipitated in hollow spaces.

References

1. ^ Proenza, J.A. et al. (2008) Garnierite mineralization from Falconda Ni-laterite deposit (Dominican Republic), Revista de la Sociedad Espanola de Mineralogia. Macia no.9 Septiembre 08. http://www.ehu.es/sem/macla_pdf/macla9/macla9_197.pdf

• Brindley, G.W. and P. T. Hang (1973) The nature of garnierite. structure, chemical composition and color characteristics, Clays and Clay Mineral. 21, 27-40.

This article about a specific silicate mineral is a stub. You can help Wikipedia by expanding it.v · Categories: Nickel minerals Magnesium minerals Silicate minerals Silicate mineral stubs Wikimedia Foundation. 2010. Игры ⚽ Нужно сделать НИР? William Henry Draper III Commonwealth Fund Look at other dictionaries: GARNIÉRITE — Phyllosilicate du groupe de l’halloysite découvert par l’ingénieur français Garnier dans les minerais nickélifères de Nouméa, en Nouvelle Calédonie. La garniérite a pour formule chimique: (Ni,Mg)3[Si25](OH)4. Sa composition est variable, avec… …   Encyclopédie Universelle Garniérite — Thio Nouvelle Calédonie La garniérite n’est pas une espèce minérale mais un terme générique qui recouvre plusieurs espèces nickélifères, de phyllosilicates. Leur teneur élevée en nickel les fait rechercher comme minerai de ce métal. Il s’agit de… …   Wikipédia en Français Garnierite — Garniérite Garniérite La garniérite (ou falcondoïte ou genthite) est un phyllosilicate double de nickel et de magnésium, de formule (Ni,Mg)4Si6O15(OH)2·6H2O, qui appartient au groupe de la sépiolite. Sa teneur moyenne en nickel est 2 à …   Wikipédia en Français Garnierite — Gar ni*er*ite, n. [Named after the French geologist Garnier.] (Min.) An amorphous mineral of apple green color; a hydrous silicate of nickel and magnesia. It is an important ore of nickel. [1913 Webster] …   The Collaborative International Dictionary of English garnierite — [gär′nē ər īt΄] n. [after J. Garnier, 19th c. Fr geologist] a green, soft, amorphous mineral, hydrous nickel magnesium silicate, (Ni, Mg) 3 Si2O5 (OH) 4, that is an ore of nickel and is used as a gem …   English World dictionary garnierite — garnieritas statusas T sritis chemija apibrėžtis Bendras hidratuotų nikelio magnio silikatų pavadinimas. atitikmenys: angl. garnierite rus. гарниерит …   Chemijos terminų aiškinamasis žodynas garnierite — garnieritas statusas T sritis chemija apibrėžtis Mineralas. formulė (Ni,Mg)₃Si₂O₅(OH)₄ atitikmenys: angl. garnierite rus. гарниерит …   Chemijos terminų aiškinamasis žodynas garnierite — noun Etymology: Jules Garnier died 1904 French geologist Date: 1875 a soft mineral consisting of hydrous nickel magnesium silicate and constituting an important ore of nickel …   New Collegiate Dictionary garnierite — /gahr nee euh ruyt /, n. a mineral, hydrous nickel magnesium silicate, occurring in earthy, green masses: an important ore of nickel. [1875; named after Jules Garnier (d. 1904), French geologist; see ITE1] * * * …   Universalium garnierite — noun A green nickel ore found in fissures of weathered ultramafic rocks …   Wiktionary 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”