19th century. Probably from a goat or other ruminant.  Bezoars were believed to have the power of a universal antidote against poison. A bezoar, attractively, is a mass found trapped in the gastrointestinal system of an animal, people too occasionally. But no one is going to pay £250 for an unglamorous gastric stone and they are much more exciting than that.  Indeed, as any Hogwarts student will know, they are magical objects and do appear to have properties as antidotes to some poisons.  To quote Wikipedia rather than Bathilda Bagshot…
‘Modern examinations of the properties of bezoars by Gustaf Arrhenius and Andrew A. Benson of the Scripps Institution of Oceanography show that when bezoars are immersed in an arsenic-laced solution, they can remove the poison. The toxic compounds in arsenic are arsenate and arsenite; each is acted upon differently by the bezoars: arsenate is removed by being exchanged for phosphate in brushite found in the stones, while arsenite is bound to sulfur compounds in the protein of degraded hair, which is a key component in bezoars’
On the other hand, ‘In 1567, French surgeon Ambroise Paré did not believe that it was possible for the bezoar to cure the effects of any poison, and described an experiment to test the properties of the stone. A cook in the King's court was sentenced to death and chose to be poisoned. Paré administered the bezoar stone to the cook, but it had no effect, and the cook died in agony seven hours after taking the poison, proving that contrary to popular belief, the bezoar could not cure all poisons’
Ox bezoars are used in Chinese medicine for removal of toxins, and some were polished and set in rings as shields against the attentions of the likes of the Borgia family, but stones like this are quite rare and this is emphatically the brilliantly unique present for the aspiring wizard, or the person with a gap in their Wunderkammer.