Rock-hard 'toffee'

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Portoro marble - looking more like a dessert than a rock

The day I took this photo was a feast for the eyes and the soul; whilst a rehearsal for the following week's Trooping of the Colour was underway nearby, my Other Half and I were visiting the [then] Queen's Gallery  at Buckingham Palace, London. It was the first time we saw any of the Royal Collection. We saw a Fabergé egg for the first time, and it was as beautiful and as finely wrought as we had imagined it would be.  We saw the golden Exeter Salt, we saw sculptures carved from the finest marble, we saw paintings by Old Masters and we saw, for the very first time for either of us, sketches by Leonardo da Vinci with notes in his mirror writing!

One thing I also drank in, though, was this polished slice of Portoro marble. Stonemasons often refer to any stone that will take a polish as a marble, but Portoro is a true marble, i.e. a limestone that has been altered (metamorphosed) by heat and pressure; it comes from La Spezia in Italy, and this slice adorns the top of a very ornate (actually overly ornate to my Philistine eyes) table.  The structure of the rock shows the effects of the heat and pressure that altered it from the limestone it once was; the black in it comes from organic marine material, and the gold and fawn colours come from oxidation of that same organic matter. As it was reformed, it was pulled like toffee - but it's probably best not to try to eat it. The heat, the pressure, the stretching, doing this to solid rock!  To my eyes, though, it looks like a dessert you could get a spoon into.


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