If the bubbles are minimal the rock is called obsidian.
Is granite an extrusive igneous rock.
Intrusive igneous rocks crystallize below earth s surface and the slow cooling that occurs there allows large crystals to form.
Extrusive igneous rocks erupt onto the surface where they cool quickly to form small crystals.
Exposed to the relatively cool temperatures of the atmosphere the lava cools quickly meaning that mineral crystals don t have much time to grow.
On the other hand intrusive igneous rocks form from magma that cooled slowly deep.
However if the bubbles are tiny it s called pumice.
Igneous rocks can have many different compositions depending on the magma they cool from.
Is granite an intrusive or extrusive rock.
Igneous rocks form from magma that erupted onto the surface as lava where it cooled quickly.
Extrusive or volcanic igneous rock is produced when magma exits and cools as lava at or near the earth s surface.
Granite the equivalent of its extrusive volcanic rock type rhyolite is a very common type of intrusive igneous rock.
It contains more than 68 weight of silica in composition and is granular and coarse grained in texture.
Granite has a lot of different colors ranging from white to pink.
All magma develops underground in the lower crust or upper mantle because of the intense heat there.
For instance if an extrusive rock comes out as glass with large bubbles it s called scoria.
Some cool so.
Igneous rocks form when magma molten rock cools and crystallizes either at volcanoes on the surface of the earth or while the melted rock is still inside the crust.