Basalt fiber is natural basalt melted down and then extruded to produce filaments. It is an environmentally-friendly fabric with a superior combination of heat, acid and alkali resistance, making it an alternative to fiberglass and carbon fiber. It is used for civil engineering purposes such as tarpaulins.
Primarily a reinforcement, it is mixed with mortar used in buildings or laid under ashphalt. Since it is generally not visible, it has an unsung existence. With its alkali resistance, it is mixed with cement and used in place of iron as a foundation, leading to the increased durability of products. It is still being researched as a material and is expected to have other applications in the future.