A new box of crayons still calls to me. Its where I learned that colors wore specific nametags: aquamarine, jade, umber, siena. And now I know that Siena is siena. Technically, siena is a natural earth pigment, one of the oldest kinds of pigments that have been used by all civilizations. According to Colour, Making and Using Dyes and Pigments, published by Thames and Hudson, siena results from yellow iron oxide, geothite, with a small amount of manganese oxide mixed in. But, looking out over the roof tops in this Tuscan town, it is quite clear what place ended up the namesake.