In petrology, granite is the light-colored, coarse-grained rock formed at depth and exposed after deep erosion while basalt is the dark , fine-grained cooling stuff of many lava flows and magma intrusions. These two categories belongs to the igneous rocks. All igneous rocks formed by solidifying from hot, molten mineral material. With the process of rock-cooling, textures from very small size to those as large as pebbles may appear on the surface of these stones.

People engaged in the stone business is not so specialist as the petrologist regarding the precise name of various granite stones，or otherwise that would be difficult for them to build understandings with the general public. They tend to name granite at its broadest meanings which including any rocks from the Earth’s deep crust which is termed as Plutonic by the petrologist. As Plutonic rocks may cool over millions of years in deep underground, it can have the largest grains even to meter width compared with any other igneous stones.

Unlike sandstones which is in the classification of sedimentary rocks, granite stones don’t have layers which tells sediment forming process. The continents are the exclusive home of granitic rocks, nearly everywhere on the continents, no matter what rocks are on the surface, a drill can reach granite eventually.
All rocks on earth were originally igneous as that’s the only method entirely new rock can be formed.

In addition to being used as building materials, some kind of granite is of excellent rigidity and generally find more of its usage as for the base of  the large machinery as it can resist vibrations. As for the hardness, granite is comparatively harder than sandstones and marbles, and this makes it gain more wear resistance and thus improving it service life.

Granite is also the ideal material for marvelous memorial monuments and statues, it give people the impression of historical thickness. When there is a need for heavy ceremony, granite is prime choice for the architectures representing the ceremony.