Altarpiece unclear. Altarpieces can still broadly be divided into two types, the "reredos", which signifies a large and often complex wooden or stone altarpiece, and the "retable", an altarpiece with panels either painted or with reliefs. Retables are placed directly on the altar or on a surface behind it; a reredos typically rises from the floor. Retable-type altarpieces are often made up of two or more separate panels created using a technique known as panel painting. The panels can also display reliefs or sculpture in the round, either polychrome or un-painted. It is then called a diptych, triptych or polyptych for
Crucifixion Diptych (van der Weyden) other Crucifixion paintings have been attributed to van der Weyden: Crucifixion Diptych (van der Weyden) Crucifixion Diptych — also known as Philadelphia Diptych, Calvary Diptych, Christ on the Cross with the Virgin and St. John, or The Crucifixion with the Virgin and Saint John the Evangelist Mourning — is a diptych by the Early Netherlandish artist Rogier van der Weyden, completed c. 1460, today in the Philadelphia Museum of Art. The panels are noted for their technical skill, visceral impact and for possessing a physicality and directness unusual for Netherlandish art of the time. The Philadelphia Museum of Art describes