This type of tea, also known as Pu Er, is produced with a steaming process that provokes a non-enzymatic fermentation, different from the black teas. Before being rolled, the leaves undergo a specific type of roasting, which kills most of their enzymes. This is done in iron pans, heated to 280°C-320°C, into which the leaves are placed and then covered with straw. The straw stops the steam from escaping and allows the leaves to be steam cooked. This is essential as the leaves are old and therefore lacking in moisture. During this operation, the caffeine content of the leaves decreases. A first rolling is carried out, then the leaves are arranged in piles of about 1m high and covered with a damp cover that will keep a hygrometric level of 85%. This is the sweating process. It lasts about 24 hours and can be repeated several times. The size of the piles and the duration of the sweating period have important consequences for the tea produced; its aroma will be more, or less, enhanced. Dark teas can often be found in the form of compressed briquettes or bird's nests. They are also the only teas that improve with age and for which age can sometimes carry enormous weight when selling at auction.

See our selection of dark teas.