Setting a fragile diamond

[kenny]

What is the least stressful way to set a diamond?

I have read here that low-clarity diamonds with feathers or other interruptions to the crystal structure, and brown and pink diamonds with internal graining lines are weaker so they are more at risk for damage during the setting process.

So which setting process puts the least mechanical or thermal stress on the diamond?

Full bezel
Half bezel
Prongs
Tension Setting, parallel to, or perpendicular to the weakness
Other

I'm not asking about which protects the diamond best after setting.
I'm asking about which is most gentle on the diamond during setting.

 

[LD]

Date: 11/3/2009 1:56:00 PM
Author:kenny
What is the least stressful way to set a diamond?

I have read here that low-clarity diamonds with feathers or other interruptions to the crystal structure, and brown and pink diamonds with internal graining lines are weaker so they are more at risk for damage during the setting process.

So which setting process puts the least mechanical or thermal stress on the diamond?

Full bezel
Half bezel
Prongs
Tension Setting, parallel to, or perpendicular to the weakness
Other

I''m not asking about which protects the diamond best after setting.
I''m asking about which is most gentle on the diamond during setting.

Get drunk??????

No seriously, I don''t know the answer but do know that bezel (because they have to be folded over the gemstone - therefore putting pressure on the stone) isn''t recommended for fragile gemstones so I would rule the full bezel out and perhaps the half bezel. My guess is that prongs would be the safest BUT I guess it depends on how unstable the structure of the diamond is.

Sorry - probably doesn''t help at all!

 

[kenny]

Get drunk? Hahha.

Don't prongs involve a lot of heat?

 

[LD]

Date: 11/3/2009 2:56:32 PM
Author: kenny
Get drunk? Hahha.

Don''t prongs involve a lot of heat?

Yes but then I think all settings do - although I could be wrong. For a bezel setting you need head to bend the gold over. To create a tension setting you have to exert pressure on the diamond to hold it in place and I think heat would have to be used to achieve this.

 

[MustangGal]

I have a diamond with a crack 50% across (breaks the surface at the girdle and runs straight into the middle of the stone), and it was able to be set in a half bezel. The bench guy didn''t even seem to be worried about it breaking.

I''d love to hear what is "safest" though!

 

[LGK]

I have a diamond with an incredibly thin girdle (and in fact it has a chip on the thinnest part already) and it was safe to put it in a full bezel.

 

[kenny]

Bump.

 

[blingmyring]

Bump.

 

[denverappraiser]

There’s no short answer to the question because the setting techniques and the nature of the risk will vary so much. Rarely is any heat at all used by the way. Done carefully, nearly everything can be set at low risk and with enough bad luck, a jeweler can chip a stone doing nearly anything. If I had to rank them I guess I would prefer to prong set a fragile stone in platinum and my least favorite would be to gypsy set it (set flush with the metal) or channel set it in 18k white. True tension setting, as opposed to channel setting, is a whole different issue because certain kinds of problems make it basically impossible to do the job.

On the grand scale of stones, diamonds are more durable for setting than nearly everything else out there. Opals, emeralds,tanzanite, and even amethyst, among others, represent a significantly higher breakage risk for jewelers and are usually cut with less precision, which just aggravates the whole issue.

Neil Beaty
GG(GIA) ICGA(AGS) NAJA
Professional Appraisals in Denver

 

[kenny]

Thanks Neil.

I had no idea that during setting using platinum is less stress on the stone than gold.
I thought gold was softer.

 

[stone-cold11]

I think that depends on the exact alloy used. If it is the standard Pt950/Ir, it will be softer than most gold alloy.

 

[denverappraiser]

The reason setters like platinum better isn’t so much a matter of hardness as springiness. A bezel is pushed down over the stone using a hammer and a punch and it’s really annoying to carefully hammer a piece of metal to exactly where you want it just to have it spring back, leaving the stone loose. Platinum doesn’t do this … it stays where you put it. You still have to be careful with the hammer, of course, but you only have to do the job once rather than again and again with white gold. Prongs are basically the same thing but there’s not as much metal to move and it’s usually done with more discreet kinds of tools. With prongs it''s also easier to look at it from all directions and monitor your progress. With a bezel you can''t see the edge of the stone so there''s less direct feedback during the process of how it''s going.

Neil Beaty
GG(GIA) ICGA(AGS) NAJA
Professional Appraisals in Denver