granite
Large crystals are diagnostic of an intrusive igneous rock, as large crystals form as the source magma cools slowly.
10
Two types of igneous rock are intrusive (also called plutonic) and extrusive. There is also porphyry rock which is partly intrusive and partly extrusive. Porphyry rock has large crystals embedded in a mass of much smaller crystals. The large crystals formed underground as does intrusive rock, and were carried in lava when it erupted. The mass of smaller crystals formed around the large crystals when the lava cooled quickly above ground, as does extrusive rock.
Igneous rocks will develop large crystals is they cool slowly underground.
Gabbro.
A rock with large crystals indicates that the rock cooled slowly. It is referred to as a phaneritic texture when a rock forms this way.
granite is a hard rockk madeof crystals
porphyry
A rock with large crystals indicates that the rock cooled slowly. It is referred to as a phaneritic texture when a rock forms this way.
sedimantry
Large crystals are diagnostic of an intrusive igneous rock, as large crystals form as the source magma cools slowly.
It's an igneous porphyry.
granite
Quartz
10
Two types of igneous rock are intrusive (also called plutonic) and extrusive. There is also porphyry rock which is partly intrusive and partly extrusive. Porphyry rock has large crystals embedded in a mass of much smaller crystals. The large crystals formed underground as does intrusive rock, and were carried in lava when it erupted. The mass of smaller crystals formed around the large crystals when the lava cooled quickly above ground, as does extrusive rock.
intrusive rock