Portfolio diversification: Art: high return (~14%), low liquidity (3-7 yrs)

found this one interesting, as it has above-average performance (about 14% annualized) downside: low liquidity: can short after painting is sold which happens on average after 3-7 years. Nevertheless, seems like an interesting diversification, especially regarding low correlation to most other assets e.g. stocks, other commodities etc.

Low liquidity and high std. deviation in return can also be reduced by making many tiny investments (more regular payouts & reduced deviations by taking mean).