Yixing teapots are intended for puer, black, and oolong teas. Vietnam also produces black and oolong teas in lesser quantities. It is a heavily oxidized, dark oolong tea. Recommended brewing techniques for oolong tea vary widely. The different types of Chinese tea include black, white, green, yellow, oolong, and dark tea. Different styles of oolong tea can vary widely in flavor. These are usually served alongside of pots of oolong or jasmine tea. It is processed as black, green, white and oolong tea. Jin Xuan (; pronounced ) is a variety of oolong tea developed in 1980. It will produce Suntory Oolong Tea, Boss and Orangina. Both are major historical centers of oolong tea production in China. The tea is also known as #12 or as "Milk Oolong" (Nai Xiang). The term "blue tea" () in French is synonymous with the term oolong. Darjeeling oolong in second flush is more accepted worldwide. Reputable dealers usually declare whether it is a natural or flavored oolong.