Mudstone thin section microscope slide composed of predominantly clay minerals and organic matter with occurrences of silt grade quartz. Mudstone is a very fine grained sedimentary rock composed of clay minerals & silt sized quartz grains that lacks the fissility of shale. The hand specimens are black in colour indicating a high organic component and the thin sections support this. This material was laid down in a low energy, oxygen starved environment during the Carboniferous Period and it was collected from Lancashire, UK. The glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy, petrology & educational use.