| 释义 |
ramsdellite Min.|ˈræmzdəlaɪt|
[f. the name of Lewis S. Ramsdell (1895–1975), U.S. mineralogist + -ite1.]
An oxide of manganese, MnO2, similar to pyrolusite, occurring as orthorhombic crystals and platy masses of a grey to black colour.
1943Fleischer & Richmond in Econ. Geol. XXXVIII. 278 Ramsdellite. [Note] This is the first use of this name in print. The mineral was described in 1932 by Ramsdell..as a possible dimorph of pyrolusite. 1965G. J. Williams Econ. Geol. N.Z. xiii. 190/2 Coombs (in Reed, 1959) mentioned the existence of ramsdellite (a polymorph of pyrolusite) at Taieri Mouth in ore which consists of pyrolusite with minor manganite. 1969Econ. Geol. LXIV. 221/2 Ramsdellite can very easily be mistaken for pyrolusite. 1972Mineral. Rec. III. 210 Ramsdellite, a relatively common mineral in the Chihuahua geodes, is found as fibrous dendritic masses on quartz but is more commonly found growing as well developed crystals on goethite blades in two different habits. |