pyrolusite

American  

[pahy-ruh-loo-sahyt, pahy-rol-yuh-sahyt] / ˌpaɪ rəˈlu saɪt, paɪˈrɒl yəˌsaɪt /

noun

1. a common mineral, manganese dioxide, MnO 2 , 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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pyrolusite British  

/ ˌpaɪrəʊˈluːsaɪt /

noun

1. 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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Etymology

Origin of pyrolusite

1820–30; pyro- + Greek loûs ( is ) washing + -ite ¹

Example Sentences

While studying the action of hydrochloric acid upon the mineral pyrolusite, in 1774, Scheele obtained a yellowish, gaseous substance to which he gave a name in keeping with the phlogiston theory then current.

From An Elementary Study of Chemistry by McPherson, William

Manganese is found in nature chiefly as the dioxide MnO2, called pyrolusite.

From An Elementary Study of Chemistry by McPherson, William

Generally resembles pyrolusite, but is distinguished from it by its superior hardness.

From The Elements of Blowpipe Analysis by Getman, Frederick Hutton

How does pyrolusite effect the decolorizing of glass containing iron?

From An Elementary Study of Chemistry by McPherson, William

Its ores occur abundantly in nature as the minerals pyrolusite, manganite, etc.

From The Gutenberg Webster's Unabridged Dictionary Section M, N, and O by Project Gutenberg