Two white doves: Releasing two white doves symbolises the journey of a husband and wife and their promise to support and love each other for a lifetime.Source www.bellaonline.com
Throwing rice: represents wishing the couple good luck and prosperity.
Something old, something new, something borrowed, something blue: There is an additional part to that saying which is usually left off, 'And a sixpence in her shoe'.The 'something old' should be provided by someone who has been happily married for some time and, therefore, this luck will be transferred to the new couple. It also signifies the link between the bride and her family.
Something new: represents hope for the future.
Something borrowed: should be something of value like jewellery to guarantee wealth and prosperity.
Something blue: the colour signifies fidelity, purity and love and that is why it's used.
Silver sixpence: a silver coin should be worn in the heel of the left shoe to ensure wealth and prosperity.
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Jumping the broom: signifies the wife's commitment to clean the courtyard of the new home she has joined and her commitment to the home overall. It also determines who would be head of the household as the person who jumps the highest would get the job.
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Throwing the bouquet: is said to have grown out of a 14th-century French tradition where it was considered good luck to get a piece of the bride's gown, therefore guests would grab at the bride's gown to rip a fragment.The tradition developed to the point where the bride would begin throwing other personal items at her guests to preserve the dress.
Source: www.hudsonvalleyweddings.com/g