Saffron is the most expensive spice in the world.
150 flowers and substantial labor are needed to produce a single gram of saffron; it's only as affordable as it is because harvesters aren't paid much at all.
Saffron is a spice derived from the flower Crocus Sativus, commonly known as Saffron Crocus. Saffron crocus grows to 20–30 cm (8–12 in) and bears up to four flowers, each with three vivid crimson stigmas, which are the distal end of a carpel. More than 100,000 of these are needed for one pound of the spice. Saffron's aroma is often described by connoisseurs as reminiscent of metallic honey with grassy or hay-like notes, while its taste has also been noted as hay-like and sweet.
The crocus sativus stayed in bloom only for about three to four weeks. The stigmas have to be harvested by hand, when the stigmas are dried, they are called saffron. The higher the coloring strength of the saffron, the less you have to use in a dish to achieve the required effect. The flowering period of saffron starts during middle of late October and lasts until the second week of November. However, the number of saffron flowers and the time of blooming in any year are dependent upon the temperature prevalent in spring and autumn and upon the amount of rainfall.