Bones like many other natural instruments have always been used in ritualistic.
In many cultures they are also used as a fetish or a place of passage for spirits.
There are different practices that use bones as a ritual means and not only for necromancers / necromancers, in witchcraft and folk magic their use is as a means to establish contact with the spirit of the animal and work with it.
In fact it is quite common to create jewelry with animal components, including feathers, bones or skins.
Different customs in the tribes of the world often see their own (human) sometimes fallen teeth used as necklaces to remain connected to a part of their being and their spirituality (the custom of preserving milk teeth for example in some cultures has arrived up to us today) and those of others (and not only sometimes even bones and hair) to acquire their potential, like wearing and carrying animal bones you can acquire the attributes and powers of the animal to which they belong.
Some of them, instead, as vehicles of transformation, were used bones, hair, feathers or any component for transmutation rituals and to try to be possessed by the spirit of the vehicle used.
It was also customary in different cultures in America and Canada to use bones as a ritual form by shamans and tribal healers in true healing rituals using bone components as well as transmutation practices. Also present in Europe are different uses of bones in ritualistic or divinatory form.
There are instead multiple types of divination with bones and the majority practiced today is performed in Africa and Asia.
One such example is the oracular bones, use the bones or shells of sometimes engraved animals to ask questions and have responses.
Due to the great importance given in China, some bones used for this type of ritual were unearthed, chopped and used in traditional Chinese medicine.
Instead with regard to necromancy (gr. Νεκρομαντεία; but νεκρόμαντις next to νεκυόμαντις; lat. Necromantīa). - It is, as the name implies, that form of divination which consists in consulting the dead.
But in the proper sense it is so called the evocation of the spirits or souls of the departed. There are examples of this form in the current ethnography of all parts of the world and, in antiquity, of every time and place.
Necromancy comes from the Middle Ages identified as a totally negative practice also because of the sacrificial bones and also associated with the evocation of non-benevolent spirits and demons.
Nowadays in some countries it is still part of the mourning process to perform rituals and work spiritually as a tribute to the bones of loved ones, especially in Asian cultures and parts of Africa.
In some parts of Canada and the United States instead it is legal to possess human bones (obviously if obtained in complete legality and not the result of theft).
It is therefore important to emphasize the importance given to the work on bones since ancient times and their use, which varies greatly according to cultures and traditions.