Investing habits of wealthy black families

The wealth gap between black and white families has been well documented. As much as marriage and education, race has become one of the key factors of wealth in America.

But even among wealthy white and wealthy black families, there are large gaps and pronounced differences in investing and wealth holdings. According to a study by Credit Suisse and Brandeis University's Institute on Assets and Social Policy, and highlighted in the Harvard Business Review, wealthy black American families invest more conservatively than their white peers. And that conservatism may be slowing their wealth creation relative to white families.

Businessmen exiting Wall Street subway station
Fuse | Getty Images

Among the richest 5 percent of Americans, black Americans have earned roughly 60 percent what white Americans earned over the last 30 years, according to the study. White families with a net worth of $356,900 would be in the 72nd percentile among white families. Among black families, $358,450 would be enough to rank in the 95th percentile of their peers. Yet wealth among blacks is even more concentrated—the top 10 percent hold 67 percent of the wealth held by all blacks, compared with the top 10 percent holding 51 percent among white families.

Read MoreTop 5 bachelor billionaires

There are some core similarities between wealthy white and wealthy black families. Compared to the broader population, both groups are more likely to be older, college educated, married and either retired or running their own business.

Yet there are pronounced differences in how they invest. The wealthiest 5 percent of black families are slightly less likely to own stocks, bonds and other financial assets. They are more likely to own safer assets and cash equivalents, like CDs, savings accounts and life insurance.

Wealthy black Americans have more of their wealth in real estate, according to the study. Not including their primary residence, wealthy black families hold 41 percent of their nonfinancial assets in real estate, compared with about 22 percent for wealthy white families. When primary residences are included, the figures rise to 57 percent for wealthy black families and 34 percent for comparable white families.

Read MoreWho gave away the most money in 2014?

Breaking into the 1%
Breaking into the 1%   

Wealthy black families are also less likely to hold equity in businesses. Both groups are frequent business owners— about 23 percent own businesses. Yet wealthy white families hold 37 percent of their nonfinancial assets in businesses, compared with 9 percent of wealthy black families. Put another way, white business owners are investing in their businesses at a rate seven times higher than black business owners.

This conservative approach to investing and wealth creation among wealthy black families may be slowing their rise to greater wealth, the researchers said. But there are good reasons for their risk-aversion: black families are less likely to stay at the top once they get there, according to studies.

Read MoreConnecticut to rich: Please don't leave

Of the black families who were in the top-third of wealth in 1984, 8 percent had fallen into the bottom third by 2009. That's eight times more than white families. Plus, only 7 percent of black families benefit from inheritance compared with 36 percent for white families.

The study suggests that the lack of diversity on Wall Street may also play a role.

"Wall Street lacks African-American representation in sales or advisor roles, compared with life insurance or real estate brokers. Higher trust and comfort levels among people from the same cultural and racial background are common and financial institutions efforts can affect both access and household interest," the study said.