Kalkkikivi

Kalkkikivi is the Finnish term for limestone, a sedimentary rock composed primarily of calcite (calcium carbonate). It forms mainly through the accumulation and lithification of carbonate shells and skeletons of marine organisms, such as corals, foraminifera, and bivalves, or by direct precipitation of calcium carbonate from water in warm, shallow seas. The rock can be fossiliferous or composed of microcrystalline or crystalline calcite, and it often occurs in layered beds.

Physically, kalkkikivi ranges in color from white to gray or beige and has a Mohs hardness around 3. It reacts readily with dilute acids, effervescing when exposed to hydrochloric acid. Porosity and permeability vary; karst features such as caves and sinkholes can develop in areas of extensive limestone.

Occurrence and use: Limestone occurs in many parts of the world, including in bedrock sequences that are quarried for industrial purposes. In Finland, kalkkikivi has historical and modern economic importance as a dimension stone and as a source of lime for cement and agricultural liming. Its properties—ease of cutting, durability when properly quarried, and white to pale colors—make it a favored building material in different architectural styles.

Environmental aspects: Quarrying limestone can affect landscapes and groundwater, especially where karst features are present; careful management is required to mitigate water contamination and land disturbance.