In what appears to be a few sections cribbed from the introduction to her new book, Art as an Investment?, Melanie Gerlis warns against the illusion that art is an investable asset:

Art is, quite possibly, the least commoditised asset in the investment universe, offering the potential for great returns but also—as is rarely explained by its market proponents—subject to enormous risk.

Could it be that the hidden risks that Gerlis so ably describes are precisely what has begun to attract so many individual—as opposed to institutional—players to the art market? Like the booming interest in poker, a game that has also become a profession for thousands of players and an investment for their backers, art’s popularity as an investment seems to come as much from its alluring combination of skill and luck.

Indeed, though poker requires a sophisticated knowledge of the cards, the statistical probabilities of various hands and the strategy of betting, at the top level the game is more one of psychology and character than math. Something similar seems to take place at the very top of the art market where price is determined by a complex mixture of personality and culture than a pure calculation of return.

Then, again, most investors will tell you the same thing about other illiquid investment markets.

Is art really a good investment? (The Art Newspaper)