Wuyi oolong tea can be graded according to where it is grown:
Zheng Yan – “Center rock tea.” The soil consists solely of weathered rock soil. The soil composition changes out side of this region creating a noticeably different flavor from tea grown inside of it.
Ban Yan – “Half rock tea.” On the edge and in the surrounding foot hills of the Zheng Yan area. The essential qualities of yan cha flavor are less apparent than tea grown in Zheng Yan but are still recognizable. Besides growing the famous cultivers, this is the place where many not so famous teas, but still mysterious and special in their own right are grown, like Shui Xian and Ba Xian.
Zhou Cha – “River bank tea.” Tea grown near the banks of Zhou and Huangbo Rivers. The quality is considered to be half that of Zheng Yan teas.
Outside the Mountain
The highest quality tea is Zhengyan Cha. It grows in the middle of Crags in what's called the "Three Valleys and Two Ravines".
Only Zhengyan Cha has the famous Rock-like flavors (Yanyun). The next gradeBanyan Cha has much weaker Yanyun.