pyrolusite

[ pahy-ruh-loo-sahyt, pahy-rol-yuh-sahyt ]

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.

pyrolusite

/ 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

Word History and Origins

Origin of pyrolusite¹

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

Word History and Origins

Origin of pyrolusite¹

C19: from pyro- + Greek lousis a washing + -ite ¹, from its use in purifying glass

Example Sentences

The same pyrolusite (binoxide of manganese) cylinder used with the same thin rod of zinc will precipitate 75 per cent.

From Project Gutenberg

Manganese occurs mainly as black oxide (MnO2) in the mineral pyrolusite; and, in a less pure form, in psilomelane and wad.

From Project Gutenberg

How does pyrolusite effect the decolorizing of glass containing iron?

From Project Gutenberg

As an ore of manganese it is much less abundant than pyrolusite or psilomelane.

From Project Gutenberg

Its dioxide (pyrolusite) has been known from very early times, and was at first mistaken for a magnetic oxide of iron.

From Project Gutenberg