Research / Geoscience / Language
Labradorite
A plagioclase compositional name between andesine and bytownite, frequently displaying optical iridescence (labradorescence).
Language and route: European mineralogical naming after a Canadian locality. English labradorite, named after Labrador, Canada, through mineralogical naming practice
Literal gloss: from Labrador
The name and its history
Naming attribution requires verification · Eighteenth-century mineralogical usage
- What does the word literally mean?
- The gloss ‘from Labrador’ describes the linguistic allusion. The original name and its modern scientific definition must be kept distinct.
- What did the original author mean?
- A geographically named feldspar from Labrador occurrences; its iridescent habit later became especially well known.
- Why was the name needed?
- Mineralogists sought to characterise a distinctive feldspar material found in Labrador rather than describe all plagioclases chemically.
- What evidence supported the original concept?
- Appearance and occurrence of specimens from the Labrador coast; later optical and chemical study.
- How has geology changed the concept?
- In modern petrology labradorite denotes a particular plagioclase compositional range, not a separately valid IMA mineral species. Labradorite can be grey as well as iridescent.
Further historical context
Modern mineral databases classify labradorite as a variety/compositional field rather than a standalone species.
Related names
Feldspar · Plagioclase · Albite · Anorthite · Andesine · Bytownite
Sources
- Mindat, Labradorite — Place-name origin, composition and species standing
- University of Waterloo, Feldspar overview — Teaching classification of the plagioclase series