A woman displays Bi Luo Chun green tea and Bi Luo Chun black tea (L) on Sept 13, 2011. Bi Lun Chun is a type of tea that originated in China's Jiangsu province. Bi Luo Chun black tea is fermented and thus carries a different aroma compared to the traditional Bi Luo Chun green tea. Black tea is also easier to preserve. [Photo/Xinhua]