Plate tracery, in which lights were pierced in a thin wall of ashlar, allowed a window arch to have more than one light – typically two side by side and separated by flat stone spandrels.[1] The spandrels were then sculpted into figures like a roundel or a quatrefoil.[1] Plate tracery reached the height of its sophistication with the 12th-century windows of Chartres Cathedral and in the “Dean’s Eye” rose window at Lincoln Cathedral.[2]
The earliest form of window tracery, typical of Gothic architecture before the early 13th century, is known as plate tracery because the individual lights (the glazed openings in the window) have the appearance of being cut out of a flat plate of masonry. Romanesque church windows were normally quite small, somewhat taller than wide and with a simple round-headed (‘segmental’) arch at the top. From around the 1140s, the pointed arch Gothic window (also called lancet window).