Remembrall
A glass ball the size of a large marble whose smoke turns red when its owner has forgotten something, though it never says what, and goes clear again once they remember.
A Remembrall is a glass ball a little larger than a marble, filled with smoke that turns red the moment its owner has forgotten something and goes clear again once they remember what it was. It does not say what has been forgotten, which limits its usefulness considerably. Neville Longbottom is given one by his grandmother at the start of the 1991 school year, and it goes red in his hand straight away. Remembralls are barred from the O.W.L. examination hall, along with Auto-Answer Quills and anything else that might be turned to cheating.
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