The altar may also be marked with a surmounting ciborium, sometimes called a baldachin. Beneath the chancel arch stands the high altar, under an ornate baldachin. Most Coptic altars are located under a baldachin. The altar was enclosed within a chancel screen, and covered within a four-posted baldachin. Four marble plinths form the basis of the columns that support the baldachin. Throne baldachin with ostrich feather bunches (as an oriental symbol of royal power). Thouret designed the king's throne and baldachin, opposite 's 1808 portrait of the king. The surname Baldacchino comes from the artisans who used to make the Baldachin. The new items include the sanctuary bronze baldachin and the rose stained-glass window. Such a monument with a baldachin was a first in the Renaissance. The central hall had a replica of idol under a baldachin. It was named thus because the king would sit on a throne, under a baldachin. Angels hold a little baldachin over the head, and a bird sits at the foot. The chhatra shares a similar symbolic value to the baldachin, refer image of Vishvakarman. Gian Lorenzo Bernini's St. Peter's Baldachin is the most famous of these structures.