Pu-erh tea

„Depending on the desired product and speed, from quickest and tightest to slowest and loosest, pressing can be done by a large heavy stone, carved into the shape of a short cylinder with a handle, simply weighs a bag of tea down onto a wooden board. The tension from the bag and the weight of the stone together give the tea its rounded and sometimes non-uniformed edge. Due to the manual labor involved, this method of pressing is often referred to as: "hand" or "stone-pressing", and is how many artisanal pu'er bǐng are still manufactured.“

„Mushroom shaped tea appeared in 1912. It was invented at that time in order to prevent the tea from going mouldy during the transportation. It was produced in Xia-Guan and Fo-Hai (two cities in south China) with the trademark "Bao-Yan". The production was then stopped in 1966. In 1986, the production was resumed due to the request of Buddhists in Tibet.“