In serious cases pus appears between the perichondrium and cartilage. Fibrocartilage does not have a surrounding perichondrium. In an auricular hematoma, blood accumulates between the perichondrium and cartilage. The hematoma mechanically obstructs blood flow from the perichondrium to the avascular cartilage. The nasal mucosa is intimately adherent to the periosteum or perichondrium of the nasal conchae. Within adults and developing adults, most chondroblasts are located in the perichondrium. The tragal cartilage and tragal perichondrium are also used as the graft by some surgeons. Other examples include periosteum and perichondrium of bones, and the tunica albuginea of testis. Perichondrium can be found around the perimeter of elastic cartilage and hyaline cartilage.