Oud, also known as agarwood, aloewood or jinko, is a resin that forms in Aquilaria trees, large evergreens native to southeast Asia when they become infected with a type of mould. Prior to infection, the heartwood is relatively light and pale coloured; however, as the infection progresses, the tree produces a dark aromatic resin in response to the attack, which results in a very dense, dark, resin embedded heartwood. First-grade agarwood is one of the most expensive natural raw materials in the world. A whole range of qualities and products are on the market, varying in quality with geographical location and cultural deposition. Oud oil is distilled from agarwood, and fetches high prices depending on the oil’s purity, up to 100.000 USD for a liter. One of the main reasons for the relative rarity and high cost of agarwood is the depletion of the wild resource. Agarwood gained great cultural and religious significance in ancient civilizations around the world, being mentioned throughout one of the world’s oldest written texts, from the Sanskrit Vedas to ancient chinese texts.