Star Rubies odd dimensions

I’m not sure if this is something that happens with star corundum in general since it is sold by the weight, but my latest batch of star rubies there are many that are massively oversized in height. Some of these are over 7mm tall while only being about 6x7mm. Have you ever come across stones like these? What do you do in this situation? Grinding down the bottom seems incredibly wasteful, while setting as-is I think will make them stick up much too far.
Thank you

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You’re right on all counts! Grinding it down is wasteful and adding more height makes the stone more expensive when sold by weight. As I see it, your only options are a tall setting or to grind it down.

Sometimes with a wax carving you can kind of merge a deep underside into the rest of the object and not make the setting look extra tall.

It’s a beautiful stone!


I agree with Jeff’s idea if you are Carving Waxes for the Star Rubies, as that would certainly solve the issue of the stone being too tall in the mounting. I also would not grind down the stone, as that would not only be wasteful, but it would also be a wasted opportunity:

I would like to propose that you take advantage of the extra height and lovely Ruby colouring and either create a Gallery Head to reveal some of the Ruby’s sides or make strategic Cut-Outs in the stone’s Bezel to do the same (think of Stained Glass-style patterns), either way you will have some lovely Ruby-red colouring showing through!


Great idea Jonathan! Revealing some of the side of the stone will be beautiful.



If you are, or are aquainted with a good lapidary who owns a thin-kerf diamond saw, It would be possible, though finicky, to saw the 7 mm tall stone into two 3+mm tall stones and re-cab the bottom portion, creating a second star ruby. With a 6x7 stone it might not be worth the effort, but if it’s a good color and a strong star… maybe. This is a common problem with native-cut gemstones. They are cut to preserve maximum weight, not to present the finest cut. Many moons ago I purchased a native cut amethyst from one of my best suppliers, it had luscious color, but a huge “belly” since it was cut with an eye to its weight first. I took it to a gem cutter who specialized in recutting such stones to angles individually calculated to the stone’s particular RI. He returned the amethyst, about 30% lighter, but exhibiting gorgeous color with Siberian red flashes. I showed it to my supplier the next time he traveled through and he couldn’t believe it was the same stone! It made a marvelous pendant for my wife’s next February birthday - and still gets compliments.