Carats vs. Grams


Just Ask Jeff: Carats vs. Grams? Which is best? Most people can count and are not going to pay more for a stone just because it is weighed in carats.

3 Minute Read

Carats vs. Grams? Which is best?

I have heard people complain that rough stone dealers selling by the carat are over charging. This is generally not the case and frankly people that believe so are misinformed, for want of a better term.

Would/are you going to pay more for a piece of rough just because it is weighted in carats? I seriously doubt it.Most people can count and are not going to pay more for a stone just because it is weighed in carats. The whole idea that people would pay more because a stone is weighed in carats is silly. The bottom line here is that the price of quality rough is driven by the cut stone market, not the hobby market for cut or rough stones. The hobby market is tiny compared to the commercial market. You will pay the same for the rough whether it's weighted in carats or grams, the rough will cost what it costs either way and the price you pay will usually be determined by forces in the commercial cut stone market.

The more commercially viable the rough, like blue Sapphires for example, the closer to the market price for a cut stone wholesale the rough is going to cost. That is just how it is. Why would anyone with quality commercial color Sapphire material sell it for less than they could get if they cut it? The market is just so strong for blue Sapphires that it sell immediately. I would not, assuming I could even get it, which I rarely can. Lets be honest I bet most other people would not either, I do not blame them. This goes for the miners too, by the way. There is just so much demand for blue Sapphire rough that the price for the rough is set at almost the wholesale cut stone price. Demand is the driving force. I sell both by the carat for hand selected rough and by the gram for parcels. Frankly I post by the carat on hand select rough because I figure it's an easier, clearer way to do it. I have posted by the gram on some of this type of rough in the past. But decided to just use carats because I got tired of telling people how many carats 1.58 grams were, when they asked me, and a lot of people did ask. It is just easier, for me at least. This is a catch-22 in some respects, if I post in grams I get people that want the carat weight and if I post in carats there are a few people that complain about wanting gram weights.

I think part of the problem is that some of the people complaining about the cost of per/carat pieces of rough is that they really want the parcel/gram price on a single piece of rough, which is usually cheaper. Parcels are almost always cheaper because you are buying more rough and a mix of rough, not just the one or two best pieces. These people do not want to pay the hand selected price for a top single stone and want to pick the best pieces out of a parcel at the lower parcel price. Well price is a function of the total purchased and also quality. Parcels go by the gram and there are minimums, most parcels are going to be 100's of grams if not kilos and be in the thousands of dollars for the parcels. The unit price is cheaper of course and the parcels will almost always be mixed, but the total cost/purchase is going to be higher. That is why it is called a parcel. Parcels are how almost all rough dealers and cutting houses have to buy. If you want to select the best from those parcels. It costs more money. If you want a few pieces of picked rough for the parcel price/cost (per gram), you are welcome to try, but it is not likely to happen very often. I will sell rough by the carat or gram whatever you want, but the method I use to weight the rough does not effect the pricing of the rough. It will cost the same in grams as it does in carats. If you want rough cheaper, buy more at a time and not hand selected rough, buy parcels and deal with the variety that parcels include. That is how to get the best price.


Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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