How does the Wealth Gap happen?

Wealth and Income are two very different things, but they both encapsulate the same basic issue:  the ability to afford luxuries.  Since 1962, we have seen the gap spread between White and non-White Americans.  Why is this?  

The chart below shows some of the reasoning behind the gap.  Some of it lies in inheritance or investment income, but the majority of the difference is caused by the unequal division of income in the labor market.  Essentially, White people get paid more for the same work as non-White people.