business06:11Why frankincense and myrrh are so expensiveFrankincense and myrrh are perhaps best known for their biblical connotations. But this tree sap has bee...n prized across the world for over 6,000 years. These fragrant incense pieces come from the Burseraceae family of trees and are found across the Horn of Africa and the Arabian Peninsula. But despite recent attempts to protect these trees, they could soon be headed for extinction. So what makes frankincense and myrrh so expensive?