Finally Pottermore paid Professor Snape a tribute and posted a fact file about him. Though I really hoped they would reveal his wand wood and core.>> sure his wood is ebony, but Im not entirely sure about the core. My guess is dragon heartstring
What Should Be at the Core of Your 'Harry Potter' Wand? My wand is sycamore with dragon core, thirteen inches, slightly springy!
Aspen and Dragon Heartstring. 13 1/2 inches, fairly supple. Aspen, a good wood for duelists and revolutionaries (creative, driven, subtle first, then explosive). Dragon Heartstring for sheer power. Wand length for extra flair and flourish, likes attention. Supple for adaptability, not unwilling to change his mind or opinions.