Tortoiseshell Tortoiseshell Tortoiseshell or tortoise shell is a material produced from the shells of the larger species of tortoise and turtle, mainly the hawksbill sea turtle, which is an endangered species largely because of its exploitation for the material. The large size, fine colour and unusual form of the hawksbill's scutes make it especially suitable. The distinctive patterning is referred to in names such as the tortoiseshell cat, several breeds of guinea pig, and the common names of several species of the butterfly genera "Nymphalis" and "Aglais", and some other uses. Tortoiseshell was widely used from ancient times in the West
What Love Is Made Of extremely positive about "What Love Is Made Of", describing it as "darker than anything" from "On a Mission", while calling it "slinky". The reviewer went on to commend the "irresistibly pouty" chorus. Pitchfork Media's Katherine St. Asaph commented that, in the song, the singer "sound[ed] completely enthralled, by either her lover or the music" and complimented her voice, noting that it seemed "ten times bigger than before". Jordan Sargent of "Spin" magazine called the track "exuberant" and highlighted Katy's vocal performance, which he deemed "typically fantastic", while the team from pop music website Popjustice gave "What Love Is Made Of"