How Much Is A 1Ct VS1, G?

This may seem like a reasonably easy question for someone in the jewelry industry to answer but it’s actually quite difficult if the quote is to be accurate. In fact, an accurate answer cannot be derived due to lack of information. Probability comes into play when we don’t have the information needed to make an informed decision. When we don’t have enough data, all we are left with are “reasonable guesses.” Here are just some of the things we don’t know: For starters, what type of 1ct are we talking about; a shy, full, heavy or true? What type of VS1 are we talking about; a hard, lab, bonded, paperless, partial or split? What type of G; G1, G2, G3, G4 or G5? How well proportioned is it; Class I, Class II, Class III, Class IV, Ideal, Signature, Hearts and Arrows, Eight Star, High Definition or Kaplan? (If they use one of these titles to advertise the diamond is well-proportioned, what are the specifics in angles, percentages and ratios of that brand?) Once you know the specifics (proportions), do they give you enough measurements to determine if the crown angles and pavilion angles are universal or if the diamond is warped? Please don’t forget about fluorescence. Is the diamond fluorescent? If it is, is it strong, medium or faint fluorescence? Was the diamond annealed, fracture filled, bleached, assembled or laser drilled? What equipment was used to measure the diamond? Was the equipment calibrated before it was used? Does the paperwork that comes with the diamond really match the stone? Where did the diamond come from? Is it a blood diamond? Is it a secondary market diamond? Finally, once you ask every last detail, how can you know what you’ve been told is factual?

Time for a joke. There are three men on a train–an economist, a logician and a mathematician. They have just crossed the border into Scotland and they see a brown cow standing in a field. The cow is standing parallel to the train.

The economist says, “Look. The cows in Scotland are brown.”


The logician says, “No. There are cows in Scotland, of which one at least is brown.”


The mathematician says, “No. There is at least one cow in Scotland, of which one side appears to be brown.”

How much is a 1ct, VS1, G? If you were to ask the economist, he might give you more than one answer. If you were to ask the logician, he would be smart enough to ask what type of 1ct, VS1, G you were talking about. And finally, if you were to ask the mathematician, he would say, “Did you forget about one thing? How much profit does the seller want to make?

by Fred Cuellar, author of the best-selling book “How to Buy a Diamond.” More questions? Ask the Diamond Guy®