A fiber obtained from a plant, animal, or mineral. The commercially important natural fibers are those cellulosic fibers obtained from the seed hairs, stems, and leaves of plants; protein fibers obtained from the hair, fur, or cocoons of animals; and the crystalline mineral asbestos. Until the advent of the manufactured fibers near the beginning of the twentieth century, the chief fibers for apparel and home furnishings were linen and wool in the temperate climates and cotton in the tropical climates. However, with the invention of the cotton gin in 1798, cheap cotton products began to replace the more expensive linen and wool until by 1950 cotton accounted for about 70% of the world's fiber production. Despite the development of new fibers based on fossil fuels, cotton has managed to maintain its position as the fiber with the largest production volume, although its use has fallen.