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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Placing keys on a table is considered unlucky. (Sweden)
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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Amber beads, worn as a necklace, can protect against illness or cure colds.
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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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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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An acorn should be carried to bring luck and ensure a long life.
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