Prior to Mr Ollivander’s proprietorship of the family business, wizards used a wide variety of wand cores. A customer would often present the wandmaker with a magical substance to which they were attached, or had inherited, or by which their family swore (hinted at by the core of Fleur Delacour’s wand). Mr Ollivander, however, was a purist who insisted that the best wands would never be produced merely by encasing the whiskers of a favourite Kneazle (or the stalk of a Dittany plant that once saved a wizard’s father from poisoning, or the mane of a kelpie a witch had once met on holiday in Scotland) in the customer’s favourite wood. The best wands, he believed, had cores of immensely powerful magical substances, which were expertly enclosed in specially selected and complementary wandwoods, the result to be matched to an owner with whom the wand itself felt the most affinity. While there was initially substantial resistance to this revolutionary way of crafting wands, it swiftly became clear that Ollivander wands were infinitely superior to anything that had come before. His methods of locating wand woods and core substances, marrying them together and matching them to ideal owners are all jealously guarded secrets that were coveted by rival wandmakers.