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Home Page Our resident Blackbird 'White-tail' is trying out something new; he's attempting to use the seed feeder. He's a bit too large to comfortably perch on the plastic ring around the hopper so he stands on the top of a garden light holder next to the bird table. Unfortunately from here the seed feeder is tantalisingly just out of reach. Leaf-like RockHere's an unusual rock, used as a decorative building stone. It's been used to make a kind of vertical crazy paving around the back door of a business, formerly a bar, on Little Westgate, Wakefield.Phyllite, which means a 'leaf-like rock', is a metamorphic rock. It started life as muddy sediments but was transformed when it came under pressure at a time when fold-mountains were thrown up during a continental collision. It's not as smooth as slate and it isn't so re-mineralised as schist. Like these related rocks, it's the pressures of regional metamorphism rather than heat that have transformed it. New platy minerals, such as micas, line up at right angles to the pressure. These form cleavage planes. Phyllite wouldn't normally be used as a building stone because of the risk that one of these cleavage planes would give under pressure. The surface of one of these cleavage plains often has a greasy feel. Phyllites are often greenish but this example is brownish. Perhaps this is due to oxidisation of the minerals in it?
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