Millennium Square - talking about building stones 350 million years old
The introduction to the tour about the building stones of Leeds aims to give a sense of the main building materials used in Leeds: the age of the typical stones, how they were formed and why different materials have been used through the city's development. Then we look at a range of examples from the different eras used to make city centre buildings - from pebbly old millstone grit, to smoother coal measures sandstone, Portland stone half that age, through to terracotta cooked up only a century ago - a mere blink of an eye compared with the geological timeline.
On an April Saturday, in a cool east wind, we learned the difference between 'dimension stone' and 'cladding'. Some Spanish sandstone is being clipped onto a building just round the corner from where this pic was taken. We enjoyed the 'Schiller effect' of shimmering feldspar crystals in the Larvikite on a Greek Street building while Saturday revellers revved up around us. What contrasts between the multi-coloured brick and stone buildings of the late Victorian period, the pale Marmo of Edwardian times, the grey granite of the 1971 Bank of England and the ingenious 21st century office on the corner of a Georgian street. We parted in Briggate, a street laid out in 1207 - 8 blinks of an eye before the present day.