affect of colour on integrity

[PhillipSchmidt]

I have a question about diamonds as white as D & E regarding the actual material.

I have felt for a long time that they are more brittle.

I expect warmer stones to have better looking edges to the facets, and when setting I believe I have been more careful. Moreover I expect a jumble of melee in a parcel of warmer coloured stones to be cleaner that way.

It may sound like a stupid question but I don''t know why I got that impression.

Is it just a subconscious expectation playing out, or is there some scientific fact I can apply? Maybe I spent too much time playing with ice cubes when I was a kid?

I am not about to experiment and find out, nor can I think up a decent experiment that would work, as I am talking about 10 x type chipping that can occur during setting around the tips.

Anyone?

Phillip

 

[Garry H (Cut Nut)]

That is pretty vague PS.
Not sure exactly what you are saying, but:

Diamonds with the least impurities / most perfect crystaline structure - have the best developed cleavage.

i.e. they beak best when hit precisely in any one of 4 specific directions.

But inclusions have more impact than colour. The difference in colour has very little impact.

Another possability is that you think higher colour small melee stones have worse clarity.
That is because D-E SI2 mellee will often be in the same parcel as I-J clean stones. But that is only because they have the same dollar value and merchants put them together to make clients happy; some clients think they get a bargain when they pick all the D-E stones. Others think they are clever cause they take all the pure stones (with low color)

 

[MissAva]

So the stonger diamond would be the lower color with higher clarity? I am confused, could on of ya''ll point to a place to read up on this.

 

[JohnQuixote]

It''s slight, but diamond does vary from region to region in the world. Russian crystal usually tends to be more brittle than, for instance, crystal from Angola. The usual suspects (ex thin girdles, feathers etc) are really the things to watch our for though.

 

[PhillipSchmidt]

Thanks,

John, I believe the question is as much about the source of the diamond as anything else as I suspect I am also choosing to be careful on stones that come from certain places. I.e. certain suppliers seem to have rocks that need to be handled more carefully.
In that case, the warmer melee I see, are usually cut in India and sourced from Africa. (None of them has ever shown any fluorescence, which may be related).

Interesting proposition Garry. I would go for the cleaner stones for melee, because many smaller SI stones suffer for their inclusion. Smaller stones take their colour from the whiteness of the platinum underneath so, under most lighting, and seated in polished platinum; a G will look like an E.

I am not talking about cleaving, but chipping. A claw can be just beaded down and the diamond need not be violated by steel, but in cases where the claw is shaped for affect, microscopic chipping occurs where a file was used over a diamonds sharp edges.

Q. Is there an overt relationship with whiter stones and the crystals origin? I understand the Russian ruff is typically cleaner and I suspect whiter too.

I’ll bet pink ones can be even more brittle 
Perhaps the issue is over undisclosed heat treatments (doubting).

Sorry to be so vague.

 

[Garry H (Cut Nut)]

Date: 8/11/2005 2:24:21 PM
Author: Platinumsmith
Thanks,
wrong wrong wrong
John, I believe the question is as much about the source of the diamond as anything else as I suspect I am also choosing to be careful on stones that come from certain places. I.e. certain suppliers seem to have rocks that need to be handled more carefully. Angolan diamonds are alluvial so they have survived a lot of percusion in rivers during torrential storms - only the less very heavily included and and probably less perfect crystals survive
In that case, the warmer melee I see, are usually cut in India and sourced from Africa. (None of them has ever shown any fluorescence, which may be related). warmer brown = Argyle, warmer greenish brown = Russia and warmer yellow can be any where including Africa

Interesting proposition Garry. I would go for the cleaner stones for melee, because many smaller SI stones suffer for their inclusion.you got this the wrong way round Smaller stones take their colour from the whiteness of the platinum underneath so, under most lighting, and seated in polished platinum; a G will look like an E.as you go lower, yellow gold makes lower colours below I look white - you are so very wrong on this one PS that it sounds like .....

I am not talking about cleaving, but chipping. A claw can be just beaded down and the diamond need not be violated by steel, but in cases where the claw is shaped for affect, microscopic chipping occurs where a file was used over a diamonds sharp edges. I have seen many diamonds with chipping on facet edges - but none that had microscopic chips and the idea that they came from a file is not on - you would need to be very heavy handed to do that - and it is more likely to be a big chunk than a small microscopic - otherwise we would see sapphire and ruby type wear on diamonds - and we do not.

Q. Is there an overt relationship with whiter stones and the crystals origin? I understand the Russian ruff is typically cleaner and I suspect whiter too.
All areas have clean and high color, or rejection and low colour - it just what proportions each has - Pink diamonds do improve in color when you heat them for a few hours - then revert - you are confusing corundum (ruby sapp) Why not enrol in the GAA courses PS?
I’ll bet pink ones can be even more brittle 
Perhaps the issue is over undisclosed heat treatments (doubting).

Sorry to be so vague.

 

[PhillipSchmidt]

My observations of micro-chipping is real enough. It is the same as the chipping on softer stones, but far less noticeable. I have seen it all to often and I have worked as a setter setting up to a hundred stones a day and chipped some myself, (nobody - not even the appraisers could tell, and I only new because I heard it). For this reason, I very much doubt many people would know about this. It is a case of heavy handedness and it is rare, but common enough to warrent this question. I am sure it is not in any book. When I set stones I will usually turn off the radio and unhook the phone and listen carefully because if any damage will occur it will be heard a long time before any visual damage occurs. With that in mind, I can hear sounds from whiter stones that make me believe they are more brittle.

In seating small diamonds in platinum, for pave'' eg you have a burred out concaved hole which is shiny and reflects back light. This actually lifts the colour, as small stones take in colour from behind - this is not as true of stones, say, over 10pt''s (however they are rarely set the same way). I have never tried to set melee that was lower then G or whiter so I don''t know about the affect of y/g on non-collection melee, though I suspect the end result would be yellow. I am talking about the diamonds appearing whiter, you are talking about an optical illusion. Why not rhodium plate your y/g jewellery to have the seats look whiter (pave/rubbed over/chanel set only), then polish off the rhodium where it is not needed. It makes a huge difference.

I don''t know where I have been wrong in my take of your proposition. It seems to be a matter of choice. The inclusions in small melee can really take away from the sparkle. I''d choose VS everytime if I wasn''t able to sort good melee from SI parcels.

Why am I confusing diamonds with corrundum?

I know that there is a lot about diamonds I don''t know, and if I could afford the time I definately would take a course in diaonds, but I can''t. That is why I post my observations here. Garry I am sorry that you dissagree with every point I made.

perhaps a setter could chime in?