New laser stepwise heating 40Ar–39Ar dates (415 ± 1.8 and 414 ± 2 Ma) from the Etive Dyke Swarm in the SW Grampian Highlands of Scotland indicate that the dykes are 10–20 Ma older than previously assumed. The dykes constitute the final phase of the Late Caledonian Granites in the region, which themselves define the end of the Caledonian Orogeny, therefore these dates can be taken as the end of the orogeny in this area. The dates show a temporal link between the Etive magmatism and early precious metal mineralization at Tyndrum as well as emphasizing the NW to SE diachronous nature of the end of Caledonian magmatism across Scotland.

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