I quickly knew this was marble, by the way it conducts the light when you hold it up to the sun, allowing you to see the shadow of your fingers on the other side. I wonder whether this came from the demolished church which once stood on the site, it seems like an angelic material.
Or perhaps it was from someone’s house. We used to have a marble slab in our kitchen where the teapot was kept. Tea-stained but still white, crystalline and matt from years of use, but still special. I used to think of it as a slab of sugar to go with the tea.