Vasari's Lives of the Artists Chapter VI: Luca della Robbia.

From Jacopo della Quercia to another sculptor - Luca della Robbia.

The Life of Luca della Robbia, Sculptor
[c. 1400 - 1482]
Luca della Robbia, sculptor, was born in the year 1388 [it was in fact nearer 1400], in the home of his ancestors which stands under the church of San Bernaba in Florence, and he was well brought-up so that he not only learned to read and write, but also to keep accounts wherever necessary, following the custom of most Florentines. And afterwards he was sent by his father to learn the goldsmith's trade from Leonardo di Ser Giovanni, who was the considered the most skillful master of that profession in Florence. Under his direction, therefore, Luca learned how to design and work in wax, and therefore his confidence increased, he began to make objects in marble and bronze, and because these objects turned out very well indeed, he devoted himself so completely to sculpture, altogether abandoning the goldsmith's craft, that he did nothing else but chisel all day along and sketch at night. And he did this with such zeal that on many occasions at night when his feet became cold, in order not to leave his sketching, he would warm them by placing them in a basket of wood shavings - that is, the kinds of shavings carpenters remove from boards when they work them with a plane. I am not in the least surprised by this, since no one ever becomes excellent in any profession whatsoever unless he learns while still a boy to endure heat, cold, hunger, thirst, and other discomforts; those people, therefore, who think it is possible to attain an honourable rank with all the comforts and conveniences in the world are sadly mistaken: it is achieved by staying up late and working constantly, not by sleeping!
Luca della Robbia, as Vasari writes, worked for Sigismondo di Pandolfo Malatesta at the age of fifteen to carve figures in marble. From there to Florence where he carved marble figures for a bell tower: Donatus, Plato and Aristotle, a man playing a lute, Ptolemy, and Euclid. Such was the impression he made he was commissioned to decorate an organ and a bronze door. He later chose to work in clay and discovered that by coating the clay in a glaze made from tin, lead oxide, antimony, and other compounds before being baked, the clay would last much longer and give a pleasing effect. He then went on to produce coloured clay, and then painted figures and scenes on terracotta.

Here are some of his works:

Virgin and Child with Lilies (1460-70).