Reserve heads (also known as "Magical heads" or "Replacement heads", the latter term derived from the original German term "Ersatzköpfe") are distinctive sculptures made primarily of fine limestone that have been found in a number of non-royal tombs of the Fourth Dynasty of Egypt; primarily from the reigns of pyramid-building pharaohs Khufu to Khafre, circa 2551–2496 B.C. While each of the heads share characteristics in common with each other (and some examples may be more caricature than reflecting a true-life appearance), the striking individuality of the pieces makes them some of the earliest examples of portrait sculpture in existence. Their purpose is not entirely clear; the name comes from the prevalent theory first put forward in 1903 by the German Egyptologist Ludwig Borchardt, tha