Why can Longjing before Ming Dynasty sell for 5000 Jin?

Many things are expensive because they are scarce, which is of course one of the reasons.

Longjing tea generally has high requirements for tea, including picking and frying. So it's rare.

In addition, it is because people are speculating. In China, as long as it is rare, people will speculate.

Businessmen make a package, then set up a concept and advertise to tell others how rare it is, so there is no shortage of people who are willing to take money in China.