Idunna Apples
Idunna Apples are golden or copper apples that were in the possession of The National Museum of Wizarding History. They were stolen by an unknown thief in 2010, according to the Artefacts Amiss plot chapter.
The apples are grown from golden or copper seeds, and they are considered to be extremely rare. The Museum had three of the only known apples in Europe when they went missing. Eaten in their raw form, the fruit is capable of reducing its consumer's mind to a childlike state - a cursed form of inner youth and vitality. However, the apples are especially sought after for their usage in mind and memory potions. Brews that contain the flesh or skin of an Idunna Apple can alter one's recollection; as far as erasing all negative memories and drawing one into a state of euphoria.