Recrystallization of Zircon as an Indication of Contact Metamorphism

Abstract

ZIRCON (ZrSiO₄) is generally regarded as the most refractory accessory mineral present in the common rock types¹. According to Poldervaart², incipient granulation and recrystallization of zircon when exposed to ultra-metamorphic processes can be expected only in a stage as high as the sillimanite grade. Investigations in quartzite xenoliths in the southern norite belt of the Bushveld Igneous Complex of the Transvaal (South Africa), however, indicate definitely that these processes can be caused by usual contact metamorphism and that the foregoing conceptions should be revised.