Green tea does not go through a fermentation process. The leaves are rolled and dried. They remain green, and as they come from the dryer they are put through sieves that divide them into the various grades. Finally they are packed in chests lined with aluminum foil. Oolong is prepared in South China and Taiwan from a special form of China tea plant the chesima that gives the tea a distinct flavor.
Preparation is similar to the process followed in making black tea.
Both China and oolong teas are sometimes scented with flowers such as jasmine. There is a brick tea made in China for export to inner Asia, but it is not used much elsewhere. It may consist of leaves, stalks, and twigs, or it may be made mainly of tea dust. The bulk is softened with steam and compressed into blocks. The Louisiana Purchase Exposition took place in St. Louis, Mo., in 1904.