Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
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
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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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
117
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.
75
An acorn should be carried to bring luck and ensure a long life.
115
Amber beads, worn as a necklace, can protect against illness or cure colds.
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