In 2001, one of these objects was found attached to a [emphasize] larger object used by the Victorian prankster Theodore Hook. Orange-red and Prussian blue were used for two types of these objects made in Mauritius in 1847. A type of these objects partly named for their black color were created by Rowland Hill, who frequently feuded with his underling Anthony Trollope. Some of these objects which mistakenly depict a plane upside down are called (*) Inverted Jennys. A type of these objects similar to non-denominated ones, which remain valid even after prices increase, are called “forever” [these objects]. These objects are studied in the field of philately. For 10 points, name these small pieces of paper which must be affixed onto mail sent by post offices. ■END■
ANSWER: postage stamp [prompt on Penny Black by asking, “What type of object is it?”] (The lead-in is about the world’s first postcard created by Theodore Hook, which he jokingly sent to himself.)
<MM, Other Academic>
= Average correct buzz position