Many stamps were issued during the Republic of China. There are ordinary, commemorative, special, donated, free, air, express, registered, parcel and military mail. There are also local postal stamps, revised stamps, pseudo-Manchukuo stamps, North China-occupied stamps, pseudo-Mongolia stamps, and Central China-South China-occupied stamps. More about the price. If you want to study these, you'd better go to Xinhua Bookstore to buy a catalogue of stamps of the Republic of China.