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Home Page I picked up this fragment of Gritstone at Brimham Rocks this summer. Looking at it with a pocket microscope I can see that it's made up crystals of glassy quartz and dull fleshy feldspar, held together by a natural cement. In fact the grains are so large that you can identify the minerals with the naked eye. Most are a millimetre or more in size and there's even a tiny pebble of quartz that is half a centimetre long. The grains are held together by a natural mineral cement. The rock is sandy in colour on its freshly chipped face but the weathered surfaces are brown, not just with dirt but because iron minerals in the rock have oxidised. It was laid down in a vast river delta some 320 million years ago. Writers in Gritstone CountryDaniel Defoe'The wildest part of the country is full of variety, the most mountainous places have their rarities to oblige the curious, and give constant employ to the enquiries of a diligent observer.'Emily Brontë'the gaunt thorns stretching their limbs one way, as though craving the alms of the sun.'Ted Hughes'Millstone Grit - a soul-grinding sandstone. Roof-of-the-world-ridge wind, And rain, and rain.'A. S. WainwrightBlackstone Edge . . . cairn and notice-board. The notice-board is blank and one wonders what it used to say in this dreary and God-forsaken spot. Probably YOU MUST BE MAD.'
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