Oolongs have the largest variety of teas. There are actually 5 subcategories of oolongs because of their variety of oxidation and processing. Oolong teas are arguably the most demanding teas to manufacture. First, the fresh leaves are withered for 8 hours or more. Then they are lightly bruised by rolling or shaking, which starts partial oxidation on the leaf edges. Pan firing and air drying are used to further reduce moisture content. Often the rolling and drying are interspersed, developing a unique, slow, partial oxidation. Although single leaf oolongs exist, most are made from three leaves and a bud, so very large leaves are usually a striking part of the leaf style. Oolongs can appear as tightly curled balls, or as voluminous twisting leaves. Fragrant, rich, complex and sometimes fruity. The liquor can be as light as a green tea, or almost as dark as a black tea.