One of my favorite materials is gold smalti: a chunk of glass plus a thin layer of gold and an even thinner layer of glass on top. This luscious dish of smalti was made by the Orsoni Factory in Italy, and I buy it by the ounce, even though I covet it by the ton. Someone asked me if this is the gold used in the ceiling of San Marco in Venice. I looked it up, and Orsoni has since its beginning in 1888, manufactured mosaics for the renovation of the Basilica. It supplied more than 1,000 ancient 24K gold plates that decorate the 8,000 square meters of the structure.