This sandstone breccia outcrops next to the contact of the Rum Central Complex. It consists of angular and sub-rounded fragments of gritty sandstone, sandstone, siltstone and indurated mudstone derived from the lower members of the Torridonian Group. Rare clasts of dolerite, basalt and gneiss are also found in this rock but are not visible in our thin section.
Quartz is the major mineral of this rock, but lamellar twinned plagioclase feldspar forming mineral clasts is also quite common.
The United Kingdom Virtual Microscope (UKVM) collection consists of igneous, sedimentary and metamorphic rocks from around the UK.
It is intended as a teaching resource, helping to tell the story of the common rock types and how they form, and reflecting the history of the UK at the margins of the continent of Europe. The collection is a series of teaching sets, for example igneous rocks from the North Atlantic Igneous Province and SW England; high-temperature metamorphic rocks from Scotland and low-temperature metamorphic rocks from Wales; and sedimentary rocks, including English limestones and sandstones.