Igneous Rocks With Large Crystals

There are two basic types.

Igneous rocks with large crystals.

Igneous rocks that are formed underground are called intrusive igneous rocks. In many igneous rocks large mineral crystals float in a fine grained groundmass. Igneous rocks are formed from the solidification of molten rock material. Intrusive igneous rocks crystallize below earth s surface and the slow cooling that occurs there allows large crystals to form.

The large grains are called phenocrysts and rock with phenocrysts is called a porphyry that is it has a porphyritic texture. Examples of intrusive igneous rocks are diabase diorite gabbro granite pegmatite and peridotite. Magma that cools slowly will form an igneous rock with. What are igneous rocks.

Rapid cooling results in smaller crystals while slow cooling results in large crystals. Igneous rocks contain randomly arranged interlocking crystals. They are characterized by large crystals mostly visible with the naked eye. Igneous rock derived from the latin word ignis meaning fire or magmatic rock is one of the three main rock types the others being sedimentary and metamorphic igneous rock is formed through the cooling and solidification of magma or lava the magma can be derived from partial melts of existing rocks in either a planet s mantle or crust typically the melting is caused by one or more of.

Intrusive igneous rocks are formed when the magma cools off slowly under the earth s crust and hardens into rocks. Igneous rocks are of two types intrusive plutonic rocks and extrusive volcanic rocks.