This is the centerpiece of the Arian Baptistery located in Ravenna, Italy. The Baptistery was built around the end of the 5th century. This dome depicts Jesus being baptized by John the Baptist. This Baptistery is octagon in shape and the floor of it is 2.3 meters below ground. The mosaic technique used was Byzantine but no one knows who the mosaicists were. Usually a team of people would perform different tasks to create these mosaics: painters that drew the outline in wet mortar, people cutting the tesserae, and others that came up with the original design and then set each tesserae into the wet mortar.
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