Intergranular
In common mafic igneous usage, a network of larger plagioclase laths with interstices occupied by smaller crystalline grains, especially mafic minerals.
Language and route: English scientific adjective constructed from Latin inter- plus granule. English scientific adjective constructed from Latin inter- plus granule
Literal gloss: between grains
The name and its history
No securely established individual first coiner · First geological printed use not established
- What does the word literally mean?
- Immediate route: English scientific adjective constructed from Latin inter- plus granule. Linguistic gloss: ‘between grains’. This gloss describes language, not a demonstrated early geological theory.
- What did the original author mean?
- Igneous thin-section terminology adapted the general between-grains adjective for basaltic groundmasses and networks of feldspar laths.
- Why was the name needed?
- A framework of feldspar could look superficially alike while the interstitial material differed in crystallinity and mineralogy.
- What evidence supported the original concept?
- Smaller clinopyroxene, olivine or oxide crystals filling angular openings between plagioclase laths.
- How has geology changed the concept?
- The term has broader uses outside igneous rocks; this record explicitly describes its basaltic petrological sense.
Further historical context
Igneous thin-section terminology adapted the general between-grains adjective for basaltic groundmasses and networks of feldspar laths.
A framework of feldspar could look superficially alike while the interstitial material differed in crystallinity and mineralogy.
Smaller clinopyroxene, olivine or oxide crystals filling angular openings between plagioclase laths.
The term has broader uses outside igneous rocks; this record explicitly describes its basaltic petrological sense.
Editorial qualification
The first naming act and earliest printed use have not been verified; this is an editorial reconstruction of historical need.
Related names
Intersertal · Ophitic · Subophitic · Basalt
Sources
- International Ocean Discovery Program, Expedition 360 methods — Operational definitions for igneous groundmass, flow and inclusion textures
- Geological Survey of India, Rock Texture Atlas — Photomicrographs and modern texture definitions