Glaucophane
Blue sodium-rich amphibole common in some high-pressure, relatively low-temperature metamorphic rocks.
Language and route: German Glaukophan (Hausmann), a learned formation from Greek γλαυκός (glaukós), blue-grey, and φαίνειν (phaínein), appear. German Glaukophan (Hausmann), a learned formation from Greek γλαυκός (glaukós), blue-grey, and φαίνειν (phaínein), appear
Literal gloss: blue-grey appearing
The name and its history
J. F. L. Hausmann · 1845, Journal für Praktische Chemie; relevant original not transcribed
- What does the word literally mean?
- Immediate borrowing or word-formation route: German Glaukophan (Hausmann), a learned formation from Greek γλαυκός (glaukós), blue-grey, and φαίνειν (phaínein), appear. Source form: γλαυκός (glaukós), glossed ‘blue-grey’. Conventional short gloss: ‘blue-grey appearing’. A literal gloss and the historical reason for naming must be distinguished.
- What did the original author mean?
- Hausmann described glaucophane in 1845 from the island of Syra; the Greek colour description reflects visible appearance.
- Why was the name needed?
- Mineralogists needed to distinguish an unfamiliar blue amphibole from related dark silicates.
- What evidence supported the original concept?
- Colour, cleavage, habit and locality informed early descriptions, without a plate-tectonic explanation.
- How has geology changed the concept?
- Glaucophane assemblages became associated with blueschist-facies rocks, but not every blue rock nor every blueschist-facies assemblage requires it.
Further historical context
Hausmann described glaucophane in 1845 from the island of Syra; the Greek colour description reflects visible appearance.
Mineralogists needed to distinguish an unfamiliar blue amphibole from related dark silicates.
Colour, cleavage, habit and locality informed early descriptions, without a plate-tectonic explanation.
Glaucophane assemblages became associated with blueschist-facies rocks, but not every blue rock nor every blueschist-facies assemblage requires it.
Editorial qualification
Original naming passage has not been independently transcribed; a later nomenclatural account cannot by itself establish first coinage.
Related names
Sources
- Mindat — Glaucophane — Hausmann 1845 Syra initial description and modern amphibole species
- IUGS recommendations on high-pressure rocks — modern assemblage versus facies naming safeguards
- British Geological Survey — rock classification — present petrographic framework, not evidence of historical first use