Fine art is often shielded from the ravages of an economic downturn because of its status as a safe haven for wealthy investors. But this crisis has been different.Lockdowns and social distancing measures across the globe have ruled out gatherings, making it impossible to visit galleries, hold exhibitions or strike deals at networking events – where most transactions in the art world normally occur.Sales of artworks have contracted by over a third globally in the first half of 2020, and one…