Sedimentary rocks in stones are formed by weathering and denudation of existing rocks deposited in rivers, lakes, oceans and other water bodies, such as limestone, sandstone and mudstone. Igneous rocks in stones are formed by cooling and solidification of lava deep in the earth, such as granite, basalt and andesite.
Metamorphic rocks in rocks are formed by chemical and physical changes of existing rocks at high temperature and high pressure, such as gneiss, mica schist and marble. In addition, there are some special ways to form stones. Meteorites, for example, are formed when meteorites in space hit the earth's surface. Coral stone is compressed from coral animal bones and shell fossils in the ocean. In a word, the formation of stone is closely related to geological processes and is one of the important substances in nature.
The role of stones
1. Building materials: Stone is a hard natural material, which can be used in buildings, roads, bridges and other projects, such as stone walls and stone bridges.
2. Sculpture art: Stone is a common carving material. Because of its hard texture, it can carve very beautiful sculptures.
3. Landscape: Stones are also widely used in gardens, which can be used as rockeries, stone bridges, pools and other landscapes to increase the beauty and artistry of gardens.
4. Mineral resources: Stone contains some useful minerals, such as metal ores and precious stones, which play an important role in economic development.
5. Geomantic omen and culture: In China culture, stones have some special symbolic meanings and functions, such as being regarded as a treasure trove of geomantic omen and a carrier of stone carving culture.