Uses: To collect the saffron, pick the stigmas as soon as the flowers open, before the flower has a chance to wilt. Air dry the stigmas as quickly as possible and store in a closed container away from light or heat. The stigmas are valued for both the yellow dye that can be made from them, and the cooking spice. Saffron is considered one of the most expensive spices in the world because the best way to collect the stigmas is through handpicking. Due to the lack of mechanization of this process, labor costs increase the cost of the spice. In 1998 saffron prices rose to $8.50 per gram in the United States.