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.“

„Fishy, Mouldy and Dry Flavours
All one's sense organs can be used in assessing tea, but Fishy, Mouldy and Dry Flavours it should be smelled and tasted. Most problems that arise are related to poor quality tea or poor storage. “