Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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A single magpie is considered a sign of bad luck. A Guide to the Scientific Knowledge of Things Familiar recites an old proverb concerning the incidence of bad weather when magpies forage alone and a possible scientific explanation for this.
49
Pirates believed that piercing the ears with such precious metals as silver and gold improved one's eyesight.
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It is bad luck to put new shoes on a bed (or a table) (comes from the tradition of dressing a corpse in new clothes and shoes and laying them out so everyone can give their respects) - (UK)
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An acorn at the window will keep lightning out
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An acorn should be carried to bring luck and ensure a long life.
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Placing keys on a table is considered unlucky. (Sweden)
3
When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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