年份：約1970年代 工序：熱蒸發酵(七分青) 茶廠：勐海茶廠 數量：兩片 總重量：約314g, 356g
The Big Blue Mark is wrapped in thick paper and features the special character "中". Made from coarse buds and large leaves, it underwent hot steaming fermentation, representing the last batch of tea produced by Menghai Tea Factory using antique tea as raw material. The Big Yellow Mark, wrapped in thin paper, is made with medium-sized leaves and tender buds, having undergone water fermentation. It is one of the earliest examples of this experimental fermentation technique.