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Day 26 : Folding in a phyllite containing alternating layers of psammite and pelite.  Note the differing behaviour of the competent and incompetent layers. New Harbour Group, Holyhead, Anglesey. Keele Collection.

Day 25 : This is the Mid-Devonian Chercombe Bridge Limestone Formation from Buckfastleigh in Devon. Fossil fragments and ooids are stretched out in the cleavage direction by shearing. Keele collection. 

Day 24 : A folded psammite from an unknown locality.  Note the change in fold style from rounded to angular and variation of wavelength across the sample. Keele collection.

Day 23 : A protomylonite from Stevenson Lake, Manitoba, Canada.  Quartz has reduced in grain size but feldspars remain as porphyroblastic ‘augen’. Keele Collection.

Day 22 : A slate (graphitic pelite – probably Ballachulish Slate Formation) from Onich, near Fort William in Scotland displaying a crenulation (vertical) and bedding / cleavage intersection lineation (horizontal). Keele collection.

Day 21 : Folded psammite layer in mica-schist. Folded original schistosity and new axial-planar schistosity developing. Probably from the Neoproterozic Carn Mairg Quartzite Formation, Allt Bhrachain, Camusvrachan, Glen Lyon, Scotland.

Day 20 : Here we have a mica schist, with a strong schistocity and mica mineral lineation that has been subsequently folded. Unknown locality, Keele collection.

Day 19 : Continuing the theme of strained rocks, this is a metamorphosed conglomerate with flattened pebbles from Stevenson Lake, Manitoba, Canada. Keele collection.

Day 18 : Shear zone in amphibolite. Unknown locality, Keele collection.

Day 17 : Isoclinal folds with an axial planar foliation refolded by later fold to produce type 3 interference.  Neoproterozoic New Harbour Group, from its type locality, New Harbour, Holyhead, Anglesey, Wales.  Keele collection.