Troctolite
A rock classification type
This page is currently not sponsored. Click here to sponsor this page.
About Troctolite
A gabbroid with <5% pyroxene and is composed chiefly of calcic plagioclase (e.g., labradorite) and olivine. Such rocks commonly are speckled like trout.
Synonym of: forellenstein, troutstone
Ref: AGI
Synonym of: forellenstein, troutstone
Ref: AGI
Unique Identifiers
Mindat ID:
48301
Long-form identifier:
mindat:1:1:48301:4
Similar Names
| Trogtalite | A valid IMA mineral species - grandfathered | CoSe2 |
Classification of Troctolite
Gabbro is in section 10 of the QAPF diagram.
Sub-divisions of Troctolite
Mineralogy of Troctolite
Essential minerals - these are minerals that are required within the classification of this rock:
| Feldspar > Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
| Olivine | Commonly used as a synonym for a member of the Fayalite-Forsterite Series, but more generally and properly ... |
Non-essential minerals - these minerals are common, sometimes major components, but are not always present:
| Amphibole > Hornblende | AnCa2(Z2+5-mZ3+m)(Si8-(n+m)Al(n+m))(OH,F,Cl)2 |
| Mica > Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Synonyms of Troctolite
Common Associates
Associations Based on Photo Data:
| 2 photos of Troctolite associated with Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
| 1 photo of Troctolite associated with 'Fayalite-Forsterite Series' | |
| 1 photo of Troctolite associated with Forsterite | Mg2(SiO4) |
Internet Links for Troctolite
mindat.org URL:
https://www.mindat.org/min-48301.html
Please feel free to link to this page.
Please feel free to link to this page.
References for Troctolite
Reference List:
Huang, W. T., Merritt, C. A. (1954) Petrography of the troctolite of the Wichita Mountains, Oklahoma. American Mineralogist, 39 (7-8) 549-565
Mason, Roger (1967) Electron-probe microanalysis of coronas in a troctolite from Sulitjelma, Norway. Mineralogical Magazine and Journal of the Mineralogical Society, 36 (280) 504-514 doi:10.1180/minmag.1967.036.280.04
Bowles, John F. W. (1976) Distinct cooling histories of troctolites from the Freetown layered gabbro. Mineralogical Magazine, 40 (315) 703-714 doi:10.1180/minmag.1976.040.315.04
Berg, Jonathan H. (1980) Snowflake troctolite in the Hettasch intrusion, Labrador: Evidence for magma-mixing and supercooling in a plutonic environment. Contributions to Mineralogy and Petrology, 72 (4) 339-351 doi:10.1007/bf00371343
Grant, Norman K., Molling, Philip A. (1981) A strontium isotope and trace element profile through the Partridge River Troctolite, Duluth complex, Minnesota. Contributions to Mineralogy and Petrology, 77 (3) 296-305 doi:10.1007/bf00373545
MATHISON, C. I., HAMLYN, P. R. (1987) The McIntosh Layered Troctolite-Olivine Gabbro Intrusion, East Kimberley, Western Australia. Journal of Petrology, 28 (1) 211-234 doi:10.1093/petrology/28.1.211
Hess, Paul C. (1994) Petrogenesis of lunar troctolites. Journal of Geophysical Research, 99. 19083 doi:10.1029/94je01868
Gabbro Quarry, Radau valley, Bad Harzburg, Goslar District, Lower Saxony, Germany