old-fashioned as Antwerp Mannerism came to the fore in the mid-16th century. Later the iconoclasm of the Reformation deemed them offensive, and many works in the Low Countries were destroyed. Extant examples are found mostly in German churches and monasteries. As secular works grew in demand, triptychs were often broken up and sold as individual works, especially if a panel or section contained an image that could pass as a secular portrait. A panel would sometimes be cut down to only the figure, with the background over-painted so that "it looked sufficiently like a genre piece to hang in a well-known collection of Dutch 17th-century paintings". Diptychs Diptychs were widely popular in northern Europe from the mid-15th to the early 16th century. They consisted of two equally sized panels joined by hinges (or, less often, a fixed frame); the panels were usually linked thematically. Hinged panels could be opened and closed like a book, allowing both an interior and exterior view, while the ability to close the wings allowed protection of the inner images. Originating from conventions in Books of Hours, diptychs typically functioned as less expensive and more portable altarpieces. Diptychs are distinct from pendants in that they are physically connected wings and not merely two paintings hung side by side. They were usually near-miniature in scale, and some emulated medieval "treasury art" -small pieces made of gold or ivory. The tracery seen in works such as van der Weyden's Virgin and Child reflects ivory carving of the period. The format was adapted by van Eyck and van der Weyden on commission from members of the House of Valois-Burgundy, and refined by Hugo van der Goes, Hans Memling and later Jan van Scorel. Netherlandish diptychs tend to illustrate only a small range of religious scenes. There are numerous depictions of the Virgin and Child, reflecting the Virgin's contemporary popularity as a subject of devotion. The inner panels consisted mainly of donor portraits – often of husbands and their wives – alongside saints or the Virgin and Child. The donor was nearly always shown kneeling in full or half length, with hands clasped in prayer. The Virgin and Child are always positioned on the right, reflecting the Christian reverence for the right hand side as the "place of honour" alongside the divine. Their development and commercial worth has been linked to a change in religious attitude during the 14th century,