From the Wikipedia page 
Chun Mee (珍眉) is a popular green tea. It has a dusty appearance and is generally more acidic and less sweet than other green teas. It was originally produced only in the Jiangxi province, but is now grown elsewhere. It is often referred as "9371".
Chun mee tea, together with Assam Bukial tea, has been studied to observe the rate of infusion of caffeine. The study found that caffeine diffusion through the tea leaves is a greatly hindered process.]