The Orris root is actually the roots of the iris plant. It has a number of uses but it's specifically used in the perfume business for making exotic perfumes. Orris root absolute is perhaps the most expensive of all absolutes mainly because 1 ton of Orris root only produces 2 to 3 kilos of Orris absolute. In order for extraction to take place the Orris roots must be dried for a period of 3 to 5 years. It has a unique woody smell which is pleasant and appealing.