al·​lo·​phane | \ ˈa-lə-ˌfān How to pronounce allophane (audio) \

Definition of allophane

: an amorphous translucent mineral of various colors often occurring in incrustations or stalactite forms and consisting of a hydrous aluminum silicate

First Known Use of allophane

1817, in the meaning defined above

History and Etymology for allophane

borrowed from German Allophan, borrowed from Late Greek allophanḗs "appearing otherwise," from Greek allo- allo- + -phanēs, adjective derivative from the base of phaínein "to show," phaínesthai "to become visible, appear, seem" — more at fancy entry 2

Note: The name Allophan was introduced by the German chemist Friedrich Stromeyer (1776-1835) and the mineralogist Johann Friedrich Ludwig Hausmann (1782-1859) in "Bemerkungen über den Allophan," Annalen der Physik, Band 54 (1816), pp. 120-37. The authors account for the name at the end of the article: "These components of the mineral cannot be easily surmised from its appearance. In order to point this out we suggest as its name allophane." ("Die Aeussere des Fossils wird diese Bestandtheile nicht leicht vermuthen lassen. Um hierauf hinzudeuten, bringen wir zur Bezeichnung desselben den Namen Allophan in Vorschlag.") The rare Greek word allophanḗs was most likely chosen from a dictionary; it is glossed "anders erscheinend" ("appearing to be different") in Johann Gottlob Schneider's Kritisches griechisch-deutsches Wörterbuch (2. Auflage, 1805).

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Cite this Entry

“Allophane.” Dictionary, Merriam-Webster, Accessed 11 Jul. 2020.

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