Painters had to grind up the semi-precious stone lapis lazuli in order to make ultramarine, the deep blue pigment that is the hallmark of many Renaissance paintings. The name comes from the Latin ultramarinus, meaning “beyond the sea”, because the stones were imported from mines in Afghanistan by Italian traders in the 14th and 15th century. Ultramarine was so expensive that some paintings were never finished because the painter couldn’t afford to buy more pigment! Even Michelangelo couldn’t afford it and Raphael used it only for a top coat.