The Zia is an ancient sun symbol of certain Native American peoples, especially tribes from the American Southwest.  There are four groups of rays, with four rays in each group.  The Zia believed that the giver of all good gave them gifts in groups of four.  These gifts are (for purposes of this explanation, look at the Zia like a compass - the top represents North, the left West, etc.):

North Represents:  North, South, East and West

East Represents: Spring, Summer, Autumn, Winter

South Represents: Sunrise, Noon, Evening and Night

West Represents: Childhood, Youth, Middle-age years, Old-age 

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