The sapphire on her ring is likely of Burmese or Ceylon origin; it is also untreated for color, making it worth more than it would have been otherwise. Its shape is either cushion or round, which means it is capable of putting out maximum shine and reflection.   Estimates of the ring’s value land between $25,000 and $50,000 per carat, which means that at this size, it should have set now-husband Brad Falchuk back somewhere in the region of $300,000 to $600,000. How much does a 12-carat diamond ring cost then? Based on a variety of factors, the cost of a diamond that size could go up to as much as $3 million. Sapphires cost a lot less than natural diamonds and actually make for a pleasant change as long as they possess consistently distributed hue. That may be why so many celebrities opt for sapphires.