It is possible to make serious cash by investing in art or jewellery, or even precious metals such as gold itself: just be prepared to put in some serious research.Adrian Pett, owner of Darnley Fine Art, says programmes like the BBC’s Antiques Roadshow have made it look easy. But for savers, precious things may not necessarily generate returns – or even increase in value over time.He says: “It is true that some people have bought items for very little and had huge returns, such as the..