Puerh is grown in Yunnan, China and aged in the compressed shape of a cake or brick. Originally this was for transportation purposes. Donkeys would carry the tea up to Tibet where it would be traded for horses. Tibetan horses were quite prized and those meditators and mounted warriors all really needed to stay awake, so it was a good deal all around.
There are two kinds of Puerh, ripe and raw, or Shou and Sheng. The Ripe kind is more mild energetically. It is deep and earthy, full of flavor and sometimes a favorite of coffee drinkers first switching over to tea. It can even lend itself to the Tibetan style of making tea. You can brew it as dark as you please and then add milk and ghee. Goat milk is particularly delicious. In Tibet it would be Dri milk, female Yak.
Raw Puerh gets it’s darkness and smoothness from age, so it should be aged quite a bit longer than ripe puerh. Usually it hits a good point for drinking after somewhere between 10 and 30 years of storage. Raw puerh is very strong energetically, and the young sheng is erratic and bitter.
Because Puerh is aged tea, it has accumulated a lot of dust. Just be sure to rinse the tea first. A rinse is quite simple: pour hot water on like you are making a steep, let it soak in a bit, and then pour it out.
Yunnan is farther west than the other tea growing regions of China. It’s not quite the Wild West, but China is similar to the United States in that the East was always more settled, and when you get out to the west there is more open space. The land looks different and the customs are different. In pictures Yunnan looks more like where I’m from, Southern California, than other parts of China—lots of brown dirt exposed in the terrain. It is believed to be the home of the original tea trees, and thus has a very old tradition of its own, perhaps the oldest tea tradition. You can still have Yunnan tea mixed with dried fruits and nuts in a very different kind of drink.