Tortoiseshell refers to an organic material obtained from Hawksbill Turtle shell used in jewelry manufacturing/making. Tortoiseshell consists of translucent and dark brown to yellow layers turtle shell, which was once commonly found
Visit the website of Historic New England at www.historicnewengland.org .for a photo of a vintage jewelry made of Tortoiseshell.
Author's Note: I am wondering if Tortoiseshell is still being used as jewelry material nowadays considering that Tortoise is already an endangered species and must be conserved. (See Hawksbill Turtle)