Why jewellers develop new cuts for diamonds

(The Financial Times) - When shopping for jewels, rarely will you be sold a round diamond. Instead you will buy a round brilliant diamond — the additional adjective refers to a cut invented in 1919 by Marcel Tolkowsky, which changed the way diamonds sparkled and how jewellers marketed them. A century later, however, we are witnessing the emergence of a generation of new cuts. Tolkowsky’s modern round brilliant cut was revolutionary. With 58 facets plotted to ensure maximum light return, it offered a fire and brilliance — that play of rainbow colours and icy scintillation — unrivalled by older cuts. By the mid-century, most new diamond jewellery had moved to this style of faceting, according to the Gemological Institute of America. The round brilliant remained largely unchallenged until the turn of this century, when price wars caused by the emergence of online-only diamantaires offering rock-bottom prices forced innovation. High-street jewellers with expensive overheads could not compete on price in terms of carat, clarity and colour alone and so manufacturers decided to tweak the final of the Four Cs: the cut. They invented premium-branded stones that promised additional sparkle through extra facets.