Andesite thin section microscope slide exhibiting an intermediate, fine grained groundmass with occasional phenocrysts of plagioclase feldspar.This material was collected from Borrowdale in the Lake District, UK & is of Late Ordovician age. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy, petrography and educational use.

Anorthosite is a phaneritic, intrusive igneous rock characterized by a predominance of plagioclase feldspar (90–100%), and a minimal mafic component (0–10%) including Pyroxene, ilmenite, magnetite, and olivine. These thin sections exhibit a rock which has been deformed and as such the once large plagioclase crystals have recrystallized to form much smaller crystals.

We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.

Diorite thin section slide. Diorite is a grey to dark-grey intermediate intrusive igneous rock composed principally of plagioclase feldspar (typically andesine), biotite mica, hornblende, and/or pyroxene. This particular material was collected in Cumbria.

We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.

Dunite Peridotite thin section microscope slide. In XPL view these thin sections exhibit the bright and beautiful second order interference colours of olivine. The high relief, lack of cleavage and distinctive fracturing is clearly evident in PPL view making for a very attractive thin section.

Gabbro thin section exhibiting some of the textbook features one would expect from this coarse, mafic igneous rock. These slides supplement the hand specimens nicely and are useful for interpreting the crystalisation history of the rock.

We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.

Microgranite thin section slide exhibiting the medium grained nature of this intrusive igneous rock. The crystals in microgranite are smaller than those of normal granite indicating that it cooled at a quicker rate.

We provide a full range of igneous, sedimentary, metamorphic and mineral thin sections. Click here to view them. Should you require a microscope, they can be found here.

Obsidian, also known as ‘volcanic glass’ is a felsic, extrusive igneous rock. Crystal growth is minimal / absent within obsidian due to rapid solidification rates which inhibit crystal growth thus giving the rock a glassy appearance.

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.

Snowflake Obsidian thin section microscope slides which exhibit radially clustered crystals of cristobalite within a glass matrix. Each section is made to 30 microns thickness. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy.

Volcanic tuff thin section exhibiting welded angular clasts of varying size. A degree of orientation can be identified as a result of the fallout of volcanic ejecta. Each section is made to 30 microns thickness and the glass is 46 x 27 mm in size with a cover slip.

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.