Which is the best country to buy diamonds?

I'm not sure anyone is really answering your question. Although ‘a diamond is a diamond’ the quality of the cut varies enormously. The cutters skill is in schieving the best result from the rough. In terms of ratio of pavilion depth to table size, the flatness of the table, the crown angle, the size of the cutlet, the consistency of the facets and the positioning of occlusion and feathers - and that is just for round cut stones. Although there are golden ratios the cutters skill is to compensate for the natural variances in the stone. Increasingly this have evolved into more exotic cuts with custom facet positioning and number. Many of the stones from volume polishers don't receive this level of individual attention and some smaller stones may be machine polished.

The best reputation for polishers is from Antwerp, London and New York but those stones may not necessarily be retailed in those countries given the fluidity of supply. These stones are brighter with more fire and radiance but cutting in these locations is reserved for outstanding diamonds. Observation is your friend. Look into the middle of the table and ensure there are minimal dark areas, turn the stone over and observe from the cutlet looking for uneven dispersion, compare the scintillation and fire of the stone with others.

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