One of the prominent embedded crystals of a porphyry.
It is a term for relatively large and conspicuous crystals in a finer-grained matrix or ground mass in igneous rocks.
A relatively large, conspicuous crystal in an otherwise mostly fine grained rock.
A conspicuous, usually large, crystal embedded in porphyritic igneous rock.
A large crystal of some mineral, usually much larger in size than the grains in the main mass of the rock in which it is embedded. Usually applied to crystals in igneous rocks that have had a complicated cooling history.
A large crystal in an igneous rock surrounded by a finer-grained matrix.
a large, conspicuous crystal in a porphoritic rock.
In igneous rocks, the relatively large and conspicuous crystals, in a finer-grained matrix or ground-mass.
A crystal that is significantly larger than the crystals surrounding it. Phenocrysts form during an early phase in the cooling of magma, and are crystals of minerals that crystallize at higher temperatures than the groundmass.
one of the large, conspicuous crystals of a mineral in a rock, which because of its greater size is set off from the rest of the rock.
A relatively large crystal set in the finer matrix of a volcanic rock. Such crystals grow slowly from the surrounding melt while the magma remains at depth and then are carried up as it rises to the surface and erupts.
A term used to describe large crystals embedded in a mass of finer crystals (groundmass) in an igneous rock. See ' porphyritic'.
A large crystal surrounded by a finer-grained matrix in an igneous rock.
A course crystal in the fine-grained matrix of the igneous rock called porphyry.
A crystal in lava, often apparent to the naked eye.
A larger crystal in an igneous rock that is clearly visible to the naked eye.
A phenocryst is a relatively large and usually conspicuous crystal distinctly larger than the grains of the rock groundmass of a porphyritic igneous rock. Phenocrysts often have euhedral forms either due to early growth within a magma or by post-empacement recrystallization.