How to Set Gemstones


Adjust a Setting for Gemstones that are not a perfect fit

At left, I show a pre-notched 10x8mm Oval Ring setting . the arrow will show where your notches will be on the prongs

[All settings sold on this website are pre-notched. that means pre filed for you at the manufacturer]


Here is a diagram of a gemstone

If you have a gemstone with a girdle that is wider than 1mm, the ready made pre-notched settings on this website won't fit ..........unless, you file the notches wider yourself.


you will have to get a setting custom made at your local jeweler.

To see if your setting is the correct shape/size, Place your setting over the gemstone upside down. Don't push it down .If it is the right size, the prongs will be about 1/2mm smaller than the gemstone. You want the prongs so that the setting will take a little effort to snap into place.

The stone Shown that I am setting in this ring is actually an 11x8mm, So I know I will have to adjust the setting.

As You can see from my test, the stone is too large for this setting. The setting is calibrated for a 10x8mm Oval & the stone is actually an 11x8mm

A note :

When your Gemstone is a little larger stone [atleast a 5 or 6mm size stone] the setting can be adjusted about 1mm larger or even smaller than it's listed size. you would only be adjusting one prong on each side a tiny 1/2mm.

for example if you have at stone that is a 7.5mm round you can adjust either a 7mm up or an 8mm down to fit. We are only talking about 1/4mm each prong. it would be so very close you might not even need to make an adjustment !

I Myself, have adjusted the quite a bit larger settings even more than 1mm on each prong to get a perfect fit.

Now if you decide you do need to adjust your setting to fit. You will need to carefully bend each of the four prongs in [or out as needed]as shown at left. Do this in very small steps.

Sometimes I use my little millimeter ruler & measure right into the notches of the prongs across to the opposite prong notch to decide how much to bend

Notice in the picture that you bend the length of the prong from the attached base to the end of the prong.that way it stays nice & straight.

I had to make all four prongs go out atleast a 1/2mm in this case

Test your stone again upside down as mentioned before.

When the setting looks slightly smaller than your stone. perhaps 1/2mm smaller, you can set your stone. This is done by pushing down on the upside down setting over the stone.

You should only need to apply Gentle pressure. Continue pushing until all the prongs snap into position with the girdle setting in the notches of each of the prongs. Your stone shouldn't move around easily in the setting.

If it does not fit correctly, you will have to start over & adjust the prongs again.



I didn't get a picture after adjusting it & before snapping it down, but it went on perfectly & here is the picture.



When you think it looks like all the notches are snugged againt the edge of your stone, you ain't finished yet !

you will have to bend the top of each prong in toward the center of your stone so that it covers the edge of the gemstone.

You need to bend the prong from the notch to the end of the prong in toward the center.

the tip of each prong is bent inward to cover a small portion of the gemstone.

Work your way around on opposing prongs bending a little at time

When you have done this correctly, the stone won't move in the setting..

After I think i am done........I find that The stone may LOOK like it is tight in the prongs & feel like it is tight in the prongs........ But if you look with good magnification from the side, holding it up to the light, you can see there is probably a lot more space than you think & you will have to bend in a little more.



If you don't have gemstone setting pliers like these below,

[they come with detailed instructions]

use your bent chain nose pliers on opposite prongs.




I use a pair of pliers like these to the left, that are special made for prong bending

sorry, I don't sell these

A note: Your pliers may slip as you are squeezing the prongs over the edge girdle of your stone. This might cause a scratch in the setting. If this happens you may need to polish /fine sand the scratched area.