Votive

A votive deposit or votive offering is one or more objects displayed or deposited, without the intention of recovery or use, in a sacred place for broadly religious purposes. Such items are a feature of modern and ancient societies and are generally made in order to gain favor with supernatural forces. Some offerings have apparently been made in anticipation of the achievement of a particular wish, but in Western cultures from which documentary evidence survives it has been more typical to wait until the wish has been fulfilled before making the offering, for which the more specific term ex-voto may be used. In buddhism Votive offerings as construction of stupas was a prevalent and holy practice in ancient india which can be observed in ruins of vikramshila university and other contemporary structure. Votive offerings have been described in historical Roman era and Greek sources, although similar acts continue into the present day, for example in traditional Catholic culture and, arguably, in the modern-day practice of tossing coins into a wishing well or fountain. The modern construction practice called topping out can be considered as an example of a votive practice that has very ancient roots.

In Europe, votive deposits are known from as early as the Neolithic, with polished axe hoards, reaching a peak in the late Bronze Age. High status artifacts such as armor and weaponry (mostly shields, swords, spears and arrows), fertility and cult symbols, coins, various treasures and animals (often dogs, oxen and in later periods horses) were common offerings in antiquity. The votive offerings were sacrificed and buried or more commonly cast into bodies of water or peat bogs, whence they could not possibly have been recovered. In certain cases entire ships have been sacrificed, as in the Danish bog Nydam Mose. Often all the objects in a ritual hoard are broken, possibly 'killing' the objects to put them even further beyond utilitarian use before deposition. The purposeful discarding of valuable items such as swords and spearheads is thought to have had ritual overtones. The items have since been discovered in rivers, lakes and present or former wetlands by construction workers, peat diggers, metal-detectorists, members of the public and archaeologists.

...
Wikipedia