Tsata

Tsata (Russian: цата, IPA: [ˈtsatə]) is a form of jewelry in the shape of a turned over crescent, typically made from gold or silver.

It is placed at the bottom of a riza as a part of the icon decoration in the Eastern Orthodox Church.

It is specifically attached to the riza so that it is placed under the face of a saint, and it typically fastened by its edges to the inner bottom edge of a venets (a halo or a crown above the saint's head).

Tsatas could contain a pattern (imprinted, stamped, filigree), gemstones and other design elements.

They were a part of most Holy Trinity, Jesus, Virgin Mary icons.