Where does Camphor flavor in Puerh tea come from?

„Pu-erh shape - Melon, or gold melon - Its shape is similar to tuóchá, but larger in size, with a much thicker body decorated with pumpkin-like stripes. This shape was created for the famous "Tribute tea" (貢茶) made expressly for the Qing Dynasty emperors from the best tea leaves of Yiwu Mountain. Larger specimens of this shape are sometimes called "human-head tea" (人頭茶), due in part to its size and shape, and because in the past it was often presented in court in a similar manner to severed heads of enemies or criminals.“