Placing keys on a table is considered unlucky. (Sweden)
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It's bad luck to leave a house through a different door than the one used to come into it.
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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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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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There are numerous sailors' superstitions, such as: it is considered bad luck for a ship to set sail on a Friday, to bring anything blue aboard, to stick a knife into the deck, to leave a hatch cover upside-down, to say "pig", or to eat walnuts aboard.
70
Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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An acorn at the window will keep lightning out
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