There are three different kinds of oranges: the sweet or common orange, the mandarin orange, and the sour or bitter orange. One type of sweet orange is called the blood orange. It has a pulp with a deep red color. This type of orange is grown mostly in the Mediterranean region. Mandarin oranges are grown mostly in Florida. Sour oranges are grown almost everywhere, but Spain grows most of the sour oranges used for trade. These sour oranges are mainly used to make marmalade; but they can be put to many other interesting uses- from making medicine to creating perfumes.

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