What is meant by the term blue moon

“Once in a blue moon” is a common expression that has been used for a long time, and which means 'not very often,' or 'very rarely. ' It often refers to an extra full moon; however, it has been used to describe the way the moon actually looked, when for different reasons it had turned a blueish color.
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What

La olla es de metal por que se calienta mas rápido, y las manijas son de madera por que así no se calientas y tienden a estar mas frías.