"Horace formed a kind of club of his favorites with himself at the center, making introductions, forging useful contacts between members, and always reaping some kind of benefit in return, whether a free box of his favorite crystallized pineapple or the chance to recommend the next junior member of the Goblin liaison Office."
--Albus Dumbledore (HBP4)
Crystallised pineapple, Horace Slughorn’s favorite sugary treat, is pineapple chunks soaked in sugar for days and coated with sugar crystals. Slughorn sometimes received crystallized pineapple as a gift from his collection of “favorite” people (HBP4).
Once Harry saw Slughorn buying it for himself at Honeydukes in Hogsmeade (HBP12). Crystallized pineapple symbolized his life-long love of luxury, even when Harry viewed him as a much-younger man and Tom Riddle's teacher: "sitting ...in the comfortable winged armchair in his office, his feet resting upon a velvet pouffe, a small glass of wine in one hand, the other rummaging in a box of crystallized pineapple" (HBP23).
Pineapples are traditional symbols of wealth and luck.
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