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Related to pyrolusite: pyrrhotite, psilomelane


A soft, black to dark gray mineral, MnO2, the commonest and most important secondary ore of manganese.

[German Pyrolusit : Greek puro-, pyro- + Greek lousis, a washing (from louein, to wash; see leu(ə)- in Indo-European roots).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Minerals) a blackish fibrous or soft powdery mineral consisting of manganese dioxide in tetragonal crystalline form. It occurs in association with other manganese ores and is an important source of manganese. Formula: MnO2
[C19: from pyro- + Greek lousis a washing +-ite1, from its use in purifying glass]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌpaɪ rəˈlu saɪt, paɪˈrɒl yəˌsaɪt)

a grayish black mineral, manganese dioxide, MnO2, the principal ore of manganese.
[1820–30; pyro- + Greek loûs(is) washing + -ite1]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pyrolusite - a mineral consisting of manganese dioxide; an important source of manganese
atomic number 25, manganese, Mn - a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals
mineral - solid homogeneous inorganic substances occurring in nature having a definite chemical composition
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The iron and manganese minerals in the study area were goethite, siderite, and rhodochrosite and contained a small amount of pyrite, magnetite, and pyrolusite [23].
SAED intensity profile, plotted as a function of [d.sup.-1] ([nm.sup.-1]), of the sample Mn25 presents the typical peaks of both maghemite and jacobsite [28] and the presence of manganosite and pyrolusite influences the symmetry of the peaks at 4.9 [nm.sup.-1] and 6.6 [nm.sup.-1] [28].
Subsequently when the calcination temperature was further increased to 400[degrees]C the XRD spectra attained were in agreement with pyrolusite Mn[O.sub.2] (JCPDS number 24-0735).
Manganese is found as braunite, pyrolusite, psilomelane, and rhodochrosite.
Important minerals of manganese are pyrolusite manganite and hausmannite (Roberts et al.
Manganese oxides are mainly constituted by [Mn[O.sub.6]] octahedra with (1 x n) pyrolusite pore structure in ramsdellite family, barium and manganese ore (2 x n) pore structure in psilomelane family, barium, calcium, and manganese family (3 x n) pore structure, and (1 x [infinity]) layered structure manganese oxide minerals [12, 13].
More specifically, they suggested that since manganese does not occur free in nature, it must be present within teeth as a mineral such as pyrolusite (manganese dioxide) and psilomelane (an oxide mineral of manganese and barium), both of which are described as bluish-black with a metallic appearance.
Chan, "pH-dependent mechanisms of methylene blue reacting with tunneled manganese oxide pyrolusite," Journal of Hazardous Materials, vol.
The standards selected for Mn were birnessite [([(Na, Ca).sub.0.5]([Mn.sup.4+], [Mn.sup.3+]).sub.2] [O.sub.4].1.5[H.sub.2]O), hureaulite ([(Mn, Fe).sub.5][H.sub.2][(P[O.sub.4]).sub.4].4[H.sub.2]O), manganocalcite (Mn-CaC[O.sub.3]), Mn-carbonate (MnC[O.sub.3]), Mn-sulfate (MnS[O.sub.4]), bixbyite ([Mn.sub.2][O.sub.3]), pyrolusite (Mn[O.sub.2]), and switzerite ([(Mn, Fe).sub.3][(P[O.sub.4]).sub.2].7[H.sub.2]O).
Pyrolusite has been used for adsorption of Pb, Zn and Mg ions from their aqueous solution [39].
The data points plot well within the [Mn.sup.2+] stability field, indicating that Mn is very undersaturated relative to pyrolusite (Mn[O.sub.2]; Mn concentrations are much lower than [10.sup.-6] M), and is not likely to become saturated unless highly oxidizing conditions are encountered.