The cooling rate of magma plays a significant role in determining the size of crystals.
how long it takes to cool
fracture
They are usually Medium size compared to those in Granite and compared to Basalt.
because they take longer to cool from the magma it is formed from
The speed in which a molten rock is solidified, determines the size and type of crystals.
Granite is composed of numbers of individual mineral crystals and these crystals of individual minerals can be referred to as grains. Due to the formative processes involving granite, individual mineral crystals may not have what is popularly thought of as a crystal form, although they truly are mineral crystals. Grains could also be crystals or particles of other rocks which make up some sedimentary rocks. The grain size is part of the determination of the rock's texture: fine-grained, coarse grained, etc..
The size of crystals that form granite are usually large and coarse-grained. Granite, which is mainly composed of feldspar, mica and quartz, is often used as a building material.
Crystal size in igneous rock is predominately a factor of time spent in cooling from lava or magma. Samples with relatively large crystals are the result of the magma having spent a longer amount of time at ideal crystal forming temperatures for each mineral present.
The will be large in an extrusive granite and fine in an intrusive basalt.
fracture
The rate at which magma cools determines the size of the mineral crystal.
Small, because it cools slowly
They are usually Medium size compared to those in Granite and compared to Basalt.
because they take longer to cool from the magma it is formed from
Crystal size in igneous rock is predominately a factor of time spent in cooling from lava or magma. Samples with relatively large crystals are the result of the magma having spent a longer amount of time at ideal crystal forming temperatures for each mineral present.
The speed in which a molten rock is solidified, determines the size and type of crystals.
Granite is composed of numbers of individual mineral crystals and these crystals of individual minerals can be referred to as grains. Due to the formative processes involving granite, individual mineral crystals may not have what is popularly thought of as a crystal form, although they truly are mineral crystals. Grains could also be crystals or particles of other rocks which make up some sedimentary rocks. The grain size is part of the determination of the rock's texture: fine-grained, coarse grained, etc..
Granite does not have a specified size. It may be small as a pebble or as big as a mountain. However, granite is said to be phaneritic in texture which means that the crystal sizes are large enough to see with the naked eye and are not larger than thumb-sized crystals.