Basse-taille

Basse-taille (bahss-tah-ee) is an enamelling technique in which the artist creates a low-relief pattern in metal, usually silver or gold, by engraving or chasing.

Medieval examples begin in Italy in the 13th century, with the earliest dated work being a chalice by the Sienese goldsmith Guccio di Mannaia, made for Pope Nicholas IV about 1290, which is part of the collection of the Treasure Museum of the basilica of Saint Francis in Assisi.

It is generally agreed that the late 14th century Royal Gold Cup, now in the British Museum, is the outstanding surviving example of basse taille enamel.

Then the interior area was worked, either with chasing tools, hammering and punching rather than cutting, or with chisels, to form a shallow recess to hold the enamel.

In the example illustrated with Luke's ox, the lowest lobe shows tufts of grass formed by cutting deeper into the background.

Finally the surfaces were cleaned up, made good and polished, perhaps including scraping off any bumps showing through on the reverse of the metal.