The class had mostly emptied out, and he dug through his bag, amongst his battered, overused books, for some clean vials, taking one up and decanting the potion in it. It shimmered a brilliant lilac and he nodded before capping two of them, one for his own purposes (he liked to keep a little of everything he made just to have) and one for the Professor. Once that was done, he put his cauldron to scrub by itself and then headed up to turn the vial in. There were only a few people left, one of them a particular redhead he was trying to pretend he didn't see.
He did notice, as he passed, that her potion wasn't exactly as it should be.
"You didn't grind the Valerian Root fine enough," he said a bit coldly, not certain why he was speaking to her, only that it slipped out before he could help it. Force of habit, perhaps. "It won't store well."