pyrolusite
[pahy-ruh-loo-sahyt, pahy-rol-yuh-sahyt]
- a common mineral, manganese dioxide, MnO2, the principal ore of manganese, used in various manufactures, as a decolorizer of brown or green tints in glass, and as a depolarizer in dry-cell batteries.
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Origin of pyrolusite
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pyrolusite
Historical Examples
Heated in an ignition tube yields water in abundance, otherwise it behaves like pyrolusite.
The Elements of Blowpipe AnalysisFrederick Hutton Getman
The substitution of potassium chlorate for pyrolusite is recommended when calcium chloride is present in the bittern.
How does pyrolusite effect the decolorizing of glass containing iron?
An Elementary Study of ChemistryWilliam McPherson
As an ore of manganese it is much less abundant than pyrolusite or psilomelane.
Its dioxide (pyrolusite) has been known from very early times, and was at first mistaken for a magnetic oxide of iron.
pyrolusite
- 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: MnO 2
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Word Origin
C19: from pyro- + Greek lousis a washing + -ite 1, from its use in purifying glass
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for pyrolusite
Online Etymology Dictionary, © 2010 Douglas Harper