irregular: 6 cm (2 3/8 in.)
Plaster
20th centuryAmericanStone
13th centuryFrenchTerracotta
4th millennium BCESumerianMarble from Greek island
1st century BCEGraeco-Roman
Ceramic tile, mirror tile, spray enamel, oyster shell, wood, oil stick, black soap, wax
21st centuryAmericanBronze
5th-2nd century BCEIberianPlaster
Limestone
6th century BCEGreekMolded, gray earthenware with traces of cold-painted pigments
6th centuryChineseBronze
16th centuryItalianTerracotta
GreekPlaster
20th centuryGerman