"Dushan jade" is a misnomer. It is not the true jade found  in Xinjiang, China: nephrite, a CaMg silicate (Si), nor the true jade found in Burma: jadeite, a NaAl silicate (Si).
"Dushan jade" is incorrect terminology. It does not denote genuine jade found in Xinjiang, China, which is nephrite—a CaMg silicate (Si)—nor does it refer to the true jade from Burma: jadeite, which is a NaAl silicate (Si).