Myrrh is harvested by repeatedly wounding the myrrh trees to bleed the gum, which is waxy and coagulates quickly. After the harvest, the gum becomes hard and glossy. The gum is yellowish and may be either clear or opaque. It darkens deeply as it ages, and white streaks emerge.
Myrrh gum is commonly harvested from the species Commiphora myrrha. Another commonly used name, Commiphora molmol, is now considered a synonym of Commiphora myrrha.
Commiphora myrrha is native to Somalia, Oman, Yemen, Eritrea, (Somali Region of) Ethiopia and parts of Saudi Arabia. Meetiga, the trade-name of Arabian Myrrh, is more brittle and gummy than the Somali variety and does not have the latter’s white markings.