Tea has been used since immemorial times as a currency. In China, tea was, just like salt, for centuries a monopoly of the state and hence a secure currency – not liable to major fluctuations in value. And if tea would for once not have been saleable, it could always be drunk. Slabs of tea were used as money in China, Mongolia, Tibet, Burma, and in parts of Russia, and in some places they are still in use. This slab is modern, since the perishability of the material means that genuine old slabs rarely survive in good condition.