"Ground state of the potions." Raising an eyebrow, "I didn't imagine you to be seriously asking me about colored chicken fat."
Shrugging again, this time just with his expression, "I don't suppose either way. It's possible, but, as I said, he did notice you being sharp; you'd probably have to give some account for that. Nor do I see why you'd want to, when you've individualized access to his own teacher, who can also perform it."