Blood stagnation due to cold black blood stagnation due to excess cold yellow internal excess cold damp white thick Green Purple pathogenic cold with food stagnation The purple tongue has a deeper blue color than crimson gray or black coat blood stagnation due to excess cold pale purple body gray coating A severely deficient constitution is then attacked by heat which enters the Blood level. This pale purple tongue develops from the pale tongue. yellow glossy a. pathogenic cold obstructs blood vessels b. food stagnation thin white alcoholism with wind cold attack white greasy Purple Tongue IndicationsAppearance a. alcoholism b. internal excess damp heat