Durability of GIA SI 1

[Texas Leaguer]

What is the difference between knots and twinning wisps inclusions?
They are basically the same except perhaps their size and position.
In our cutting world, dividing knots by cleaving and/or cutting can be very challenging. Actually their attachments can be extremely sturdy.

I have been reading this thread and cant help standing by Rockdiamond on his professional judgement and recommendation.

If this diamond is unique in any other property like its faint brown color (which many times display incredible bright appearances), and the knot inclusion looks rather harmless as in the image provided, i would definitely not discount it based on its inclusion solely.

Such diamonds can hide great value.
As far as breakage, there are so many weak spots which will break before such a knot comes apart.

Hello Yoram,
It is a real tribute to this forum that we have such a mixture of consumers, prosumers, and trades people with different areas of expertise. As a highly skilled and experienced diamond cutter your comments carry a great deal on this particular topic.

My expertise in diamonds is primarily in buying, selling and evaluating polished diamonds. I also have had a hand in running the jewelry manufacturing operations of the companies I have owned or worked for. So I have seen more than a few 'mishaps' in the shop .

Having said that, the diamond under discussion is quite unique from my experience. What makes it different is not just the size of the knot. What is really unusual is that it comes to the surface on the crown and the pavilion.

While I certainly agree that the mere presence of a knot in and of itself should not normally provoke a durability concern, in almost all cases (in my experience) knots are imbedded in the host diamond. Yes, they sometimes pull out on the cutting wheel because of the pressures involved in that process, but they are rarely knocked out by normal wear. In this case the large section of the diamond containing the knot is at the edge, and not fully surrounded by the supporting structure of the host diamond.

It is for these reasons that I agree with those advocating a cautious approach.

 

[diagem]

Hello Yoram,
It is a real tribute to this forum that we have such a mixture of consumers, prosumers, and trades people with different areas of expertise. As a highly skilled and experienced diamond cutter your comments carry a great deal on this particular topic.

My expertise in diamonds is primarily in buying, selling and evaluating polished diamonds. I also have had a hand in running the jewelry manufacturing operations of the companies I have owned or worked for. So I have seen more than a few 'mishaps' in the shop .

Having said that, the diamond under discussion is quite unique from my experience. What makes it different is not just the size of the knot. What is really unusual is that it comes to the surface on the crown and the pavilion.

While I certainly agree that the mere presence of a knot in and of itself should not normally provoke a durability concern, in almost all cases (in my experience) knots are imbedded in the host diamond. Yes, they sometimes pull out on the cutting wheel because of the pressures involved in that process, but they are rarely knocked out by normal wear. In this case the large section of the diamond containing the knot is at the edge, and not fully surrounded by the supporting structure of the host diamond.

It is for these reasons that I agree with those advocating a cautious approach.

Hi Bryan, when you do things mishaps happen, when you don’t, they don’t.
In general, knots popping out of their place may happen but on very rare events. Sometimes certain inclusions “only” appear visualy as knots (but they really aren’t), such inclusions near surfaces can pop out much easier. I have witnessed such inclusion pop out just by the standard cleaning method of boiling a diamond upon completion of the cutting.

Again, in general, many twinning wisps type polished diamonds are actually made of two seperate diamond twinned together with opposite grain directions (and usually accros the whole interior of the diamond). In my thirty years of experience, i never witnessed a natural separation of twinning wisps type of inclusions by accident.

Caution is good and it must be taking seriously when it comes to such valued (both monetary & emotional) purchase, so as Rockdiamond said, if they are plentiful, I might choose another. But when such fine inclusions appear on unique diamonds, I wouldn’t run and discount such a diamond because of the risk of a knot popping out.