| 释义 |
psilomelane Min.|psaɪˈlɒməleɪn|
Also -melan.
[f. psilo- + Gr. µέλαν, neuter of µέλας black.]
A common ore of manganese, a hydrated oxide, occurring in smooth black amorphous masses, or in botryoidal or stalactitic shapes.
Chemically it is a mechanical combination of the hydrated dioxide and protoxide, the latter often partly replaced by other protoxides, chiefly baryta and potash.
1831Trans. Royal Soc. Edin. II. 130 The name psilomelane..is formed in allusion to the black colour and smooth hematitic shapes of the mineral. 1870Yeats Nat. Hist. Comm. iii. (1872) 367 The principal ores of manganese are Pyrolusite and Psilomelane, both binoxides, the former anhydrous, the latter containing 1 per cent. of water.
Hence psilomeˈlanic a., of or of the nature of psilomelane; psiloˈmelanite = psilomelane.
1883Encycl. Brit. XV. 479/2 The writer found [in a manganese nodule dredged up by the ‘Challenger’ expedition]..a total of 21·04 per cent. of the psilomelanic part. 1839H. T. De la Beche Rep. Geol. Cornw., etc. 610 Psilomelanite [is found] at Upton Pyne, and near Launceston. 1879Cassell's Techn. Educ. IV. 255/1 Psilomelanite and braunite..are hydrated peroxide and sesquioxide of manganese. |