Over time a cornerstone became a ceremonial masonry stone, or replica, set in a prominent location on the outside of a building, with an inscription on the stone indicating the construction dates of the building and the names of architect, builder and other significant individuals. The rite of laying a cornerstone is an important cultural component of western architecture and metaphorically in sacred architecture generally.

Some cornerstones include time capsules from the time a particular building was built. The origins of this tradition are vague but its presence in Judeo-Christian countries can be associated with one quotation from the Old Testament ( ) cited six times in the New Testament ( , , , , and ) .

History

In ancient buildings, the foundation stone was placed at the north-east corner of the structure.Fact: date=March 2009 This was thought to be an auspicious position.

Often, the ceremony involved the placing of offerings of grain, wine and oil on or under the stone. These were symbolic of the produce and the people of the land and the means of their subsistence. This in turn derived from the practice in still more ancient times of making an animal or human sacrifice that was laid in the foundations.

Frazer (2006: p.106-107) in The Golden Bough charts the various propitiary sacrifices and effigy substitution such as the shadow, states that:

Nowhere, perhaps, does the equivalence of the shadow to the life or soul come out more clearly than in some customs practised to this day in South-eastern Europe. In modern Greece, when the foundation of a new building is being laid, it is the custom to kill a cock, a ram, or a lamb, and to let its blood flow on the foundation-stone, under which the animal is afterwards buried. The object of the sacrifice is to give strength and stability to the building. But sometimes, instead of killing an animal, the builder entices a man to the foundation-stone, secretly measures his body, or a part of it, or his shadow, and buries the measure under the foundation-stone; or he lays the foundation-stone upon the man's shadow. It is believed that the man will die within the year. The Roumanians of Transylvania think that he whose shadow is thus immured will die within forty days; so persons passing by a building which is in course of erection may hear a warning cry, Beware lest they take thy shadow! Not long ago there were still shadow-traders whose business it was to provide architects with the shadows necessary for securing their walls. In these cases the measure of the shadow is looked on as equivalent to the shadow itself, and to bury it is to bury the life or soul of the man, who, deprived of it, must die. Thus the custom is a substitute for the old practice of immuring a living person in the walls, or crushing him under the foundation-stone of a new building, in order to give strength and durability to the structure, or more definitely in order that the angry ghost may haunt the place and guard it against the intrusion of enemies.