Is it normal, or usual for a heavy marijuana smoker (numerous times daily for 6+ years), to be
coughing up clear
phlegm with dark gray/brown globular matter encased in it, mainly in the mornings and randomly in small amounts throughout the day? In the mornings there are much more dark pieces in clear phlegm, and when it randomly happens throughout the day, it is just small specks or chunks encased in clear phlegm.