- a coarse-grained variety of basalt.
- any of various other igneous rocks, as diabase.
- any basaltlike igneous rock whose composition can be determined only by microscopic examination.
Origin of dolerite
1830–40; < French dolérite < Greek doler(ós) deceitful (derivative of dólos wile) + French -ite -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for dolerite
The minerals of diabase are the same as those of dolerite, viz.
The dolerite of Fair Head sends off sheets along the bedding-planes of these carboniferous strata.
The boundary between these formations is also marked by the development of masses of dolerite and clayey basalt.In the Arctic Seas
Francis Leopold McClintock
Still later, dolerite sills and sheets and dikes of granophyre and quartz felsite followed in the same region.
The terms diabase and dolerite are employed really to designate distinct facies of the same set of rocks.
- a dark basic intrusive igneous rock consisting of plagioclase feldspar and a pyroxene, such as augite; often emplaced in dykes
- any dark igneous rock whose composition cannot be determined with the naked eye
C19: from French dolérite, from Greek doleros deceitful; so called because of the difficulty of determining its composition
- See diabase.
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