As a rule, dragon heartstrings produce wands with the most power, and which are capable of the most flamboyant spells. Dragon wands tend to learn more quickly than other types. While they can change allegiance if won from their original master, they always bond strongly with the current owner.
The dragon wand tends to be easiest to turn to the Dark Arts, though it will not incline that way of its own accord. It is also the most prone of the three cores to accidents, being somewhat temperamental.
Wand-quality aspen wood is white and fine-grained, and highly prized by all wand-makers for its stylish resemblance to ivory and its usually outstanding charmwork. The proper owner of the aspen wand is often an accomplished duellist, or destined to be so, for the aspen wand is one of those particularly suited to martial magic. An infamous and secretive eighteenth-century duelling club, which called itself The Silver Spears, was reputed to admit only those who owned aspen wands. In my experience, aspen wand owners are generally strong-minded and determined, more likely than most to be attracted by quests and new orders; this is a wand for revolutionaries.