Luonnonkivilajit

Luonnonkivilajit refers to naturally occurring rocks found on Earth. These rocks are classified based on their origin, composition, and texture. The three main categories of natural stones are igneous, sedimentary, and metamorphic.

Igneous rocks form from the cooling and solidification of molten rock, either magma below the Earth's surface or lava above it. Examples include granite, basalt, and obsidian. Granite is characterized by its coarse-grained texture and presence of quartz and feldspar, making it a popular building material. Basalt, on the other hand, is a fine-grained volcanic rock often found in extensive lava flows.

Sedimentary rocks are formed from the accumulation and cementation of mineral or organic particles. This process, known as lithification, can occur through compaction and the precipitation of minerals. Sandstone, limestone, and shale are common sedimentary rocks. Sandstone is composed mainly of quartz grains, while limestone is primarily made of calcium carbonate, often containing fossils. Shale is a fine-grained rock formed from compacted mud or clay.

Metamorphic rocks are created when existing rocks, whether igneous, sedimentary, or other metamorphic rocks, are transformed by heat, pressure, or chemical reactions. This alteration occurs without melting. Marble, slate, and gneiss are examples of metamorphic rocks. Marble is formed from the metamorphism of limestone, slate from shale, and gneiss from various parent rocks subjected to intense heat and pressure. Each of these natural stone types possesses unique properties that determine their use in construction, industry, and art.