20% higher for branding and
equivalent quality maybe I wouldn't mind.
But I would have to be a massive carrot head to pay twice the price for much lower quality diamonds
Anyway, I never understood why people want a tiffany ring. Wear on your finger already can tell it's tiffany meh? If I'm not wrong, the ring box itself isn't even the famous tiffany blue, only the cardboard box is and I don't think anyone uses the cardboard box to propose...
BTW, I did go down to the tiffany boutique to take a look at what they had. Their selection criteria was obviously much less stringent - without looking at the certs for the dimensions to calculate HCA, I could already tell that there was very poor optical symmetry and a lot of light leakage. This was for a 20k plus SGD ring somemore...
If branding is important, the consensus I've gathered from talking to some of the private jewellers is that the closest branded diamond to a "super ideal" round brilliant in terms of light performance would be a Hearts on Fire diamond. Think Tian Po carries it in SG.