"Blackthorn, which is a very unusual wand wood, has the reputation, in my view well-merited, of being best suited to a warrior. This does not necessarily mean that its owner practises the Dark Arts (although it is undeniable that those who do so will enjoy the blackthorn wand’s prodigious power); one finds blackthorn wands among the Aurors as well as among the denizens of Azkaban. It is a curious feature of the blackthorn bush, which sports wicked thorns, that it produces its sweetest berries after the hardest frosts, and the wands made from this wood appear to need to pass through danger or hardship with their owners to become truly bonded. Given this condition, the blackthorn wand will become as loyal and faithful a servant as one could wish."
There are currently no characters who are known to have used Blackthorn.