U–Pb measurements on zircons from gneisses, which closely resemble Amitsoq gneisses, from nunataks from the Frederikshåbs Isblink show that they are in fact much younger, probably ca. 3000 Ma old. A direct measurement of the age of the granulite facies metamorphism in the northern part of the Fiskenaesset area, of graphic, has been achieved by U–Pb analyses on: (1) a large euhedral zircon from an ultrabasic pod considered to have crystallized during the granulite facies metamorphism; (2) zircons from the Ilivertalik granite, which is considered to have been emplaced shortly before the end of the granulite facies metamorphism; and (3) zircons from an anthophyllite–gedrite rock considered to have grown during the amphibolite facies retrogression following granulite facies metamorphism.A maximum age of 2660 ± 20 Ma for the end of the low grade amphibolite facies overprinting in the southern part of the Fiskenaesset area is given by a zircon U–Pb measurement on intrusive granitic sheets.

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