The finest rubies are rarer and more valuable than diamonds and for many the icy brilliance of the latter is no match for the colour, warmth and romance of the former. Their prices are on the rise too: the record of just under $275,000 per carat set in 2005 has since risen to over $550,000. The world’s richest source of fine rubies, Burma, is still under an embargo and the market is hungry for gemstones of that quality, particularly if they can be certified ethical.