Rhomb porphyry thin section exhibiting the textbook porphyritic texture of this rare igneous rock. The thin section shows a fine grained alkali feldspar groundmass with large phenocrysts of augite. This material was collected near Oslo in Norway.

Welded tuff thin section slide exhibiting a jumbled mass of irregularly sized broken clasts held in situ by finer ash particles which have become welded together. This material was collected from Cumbria, the original rock is likely rhyolite, and indeed in hand specimen the tuff almost still looks like rhyolite and appears to show a form of banding.