Arvidsjaur porphyry ( Swedish: Arvidsjaurporfyr) is a group of igneous rocks of intermediate to felsic composition found near Arvidsjaur in northern Sweden. ^[1] The Arvidsjaur Porphyry formed 1,870 to 1,880 million years ago during the Paleoproterozoic Era. ^[1]

Most of the porphyry have well-preserved primary structures and textures which have allowed to interpret much of Arvidsjaur porphyry to be ignimbrites. ^[2] While much of the porphyryry have rhyolite compositions some parts that are interpreted as lava flows are made up of andesite with plagioclase phenocrysts. ^[1]

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