Are feathers dangerous inclusions?

[marlowe]

Does anybody have any information on feathers as an inclusion? I’ve read that they are basically cracks in the stone in the direction of the natural cleavage. As such, my concern is that can they weaken the integrity of the stone. Make it more brittle or something? My gemologist said that if GIA has serious concerns about feathers then the stone is automatically as an I1 or lower. Anybody know about this. The stone I bought has three small feathers. It’s an SI1…

 

[neatfreak]

My understanding is that feathers are no worse than other inclusions as long as they aren''t on the girdle/edge AND/OR the stone isn''t SI2 or lower.

But that''s just what I seem to remember hearing...not necessarily 100% correct!

 

[junior35]

Date: 7/1/2007 1:07:07 PM
Author:marlowe
Does anybody have any information on feathers as an inclusion? I’ve read that they are basically cracks in the stone in the direction of the natural cleavage. As such, my concern is that can they weaken the integrity of the stone. Make it more brittle or something? My gemologist said that if GIA has serious concerns about feathers then the stone is automatically as an I1 or lower. Anybody know about this. The stone I bought has three small feathers. It’s an SI1…

Relax.You have nothing to fear from feathers. Certain rough diamonds (e.g from Brazil and Angola)have ,what we call in the industry ''gletzes'' in the outer envelope or skin of the rough diamond.These cannot be sometimes economically removed in the polishing process and so they stay .

 

[snlee]

A feather that doesn''t break the surface should be fine. Feather inclusions shouldn''t normally be a problem, especially if you discuss the location of feathers with your jeweler and he is aware of any potential problems. If the stone were a SI2 or I1, I would be more concerned about the potential for damage.

I have a feather reaching the girdle in my diamond and a prong was set right next to it. A prong tends to protect that area right next to it. You don''t want the prong directly over the feather because it''ll be putting pressure on it.

 

[JohnQuixote]

Date: 7/1/2007 1:07:07 PM
Author:marlowe
Does anybody have any information on feathers as an inclusion? I’ve read that they are basically cracks in the stone in the direction of the natural cleavage. As such, my concern is that can they weaken the integrity of the stone. Make it more brittle or something? My gemologist said that if GIA has serious concerns about feathers then the stone is automatically as an I1 or lower. Anybody know about this. The stone I bought has three small feathers. It’s an SI1…

A feather is a fissure inside a diamond. It's often caused by a crystal inside the diamond that expanded millions of years ago when it formed, or can be any space between two parallel planes in the diamond. If it doesn’t break the surface or run for a long way it likely poses no problem; remember that adiamond will never be exposed to the extremes of pressure and friction it endured during the cutting process in everyday wear... On the other hand an open feather can pose a durability risk, depending on its size and position.

Feathers are very common in SI clarities and should be considered on a case by case basis. Some are prongable but with others it may not be advisable depending on size and position. If there is a question examination by a knowledgable appraiser or other expert can provide a definite answer.

While on the subject, questions about feathers often come hand-in-hand with questions about chipping. Something we're in the habit of reminding people is that diamonds have natural cleavage planes. A knock the wrong way, especially at the girdle, may cause any diamond to chip/incur damage - feather or not. This is why having a good insurance policy is important for even the most flawless diamond.

 

[He Scores]

Once a diamond with a feather flaw has gone through the rigors of the cutting process, it is relatively safe if worn normally. Like John said, a diamond dropped or bumped on a hard surface is liable to breakage whether or not it has a flaw.

Several things during the cutting process and jewelry making process that could cause the flaw to "travel" (read, get bigger) is heat, heated oil inside an open flaw, pounding from the "bruting" (read rounding/shaping) process, vibration/heat while on the wheel and heating or pressure during the setting process.

Diamonds go through quite a bit until they reach the consumer. I wouldn''t worry that a flaw would travel in your stone.


Bill Bray
Diamond Cutter

 

[junior35]

Date: 7/1/2007 1:48:14 PM
Author: snlee
A feather that doesn't break the surface should be fine. Feather inclusions shouldn't normally be a problem, especially if you discuss the location of feathers with your jeweler and he is aware of any potential problems. If the stone were a SI2 or I1, I would be more concerned about the potential for damage.

I have a feather reaching the girdle in my diamond and a prong was set right next to it. A prong tends to protect that area right next to it. You don't want the prong directly over the feather because it'll be putting pressure on it.

I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It's not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has 'gletzes' coming out of it.That's another story.

 

[strmrdr]

Date: 7/1/2007 6:51:40 PM
Author: junior35

Date: 7/1/2007 1:48:14 PM
Author: snlee
A feather that doesn''t break the surface should be fine. Feather inclusions shouldn''t normally be a problem, especially if you discuss the location of feathers with your jeweler and he is aware of any potential problems. If the stone were a SI2 or I1, I would be more concerned about the potential for damage.

I have a feather reaching the girdle in my diamond and a prong was set right next to it. A prong tends to protect that area right next to it. You don''t want the prong directly over the feather because it''ll be putting pressure on it.

I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It''s not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has ''gletzes'' coming out of it.That''s another story.

I don''t think Bill will agree with you because I can show you a bunch of examples to prove that''s not the case.

 

[pyramid]

I remember another gemmologist years ago who wrote the same thing here as Junior. He never posted much on the forum but I remember asking him about this always being open to the surface and he said exactly the same as Junior and that internal feathers were always caused by crystals.

 

[marlowe]

Just want to say I LOVE THIS FORUM. It’s so valuable to people like me (read a book, used edu tools on this site) to be able to post questions to other self educated buyers and also pros in the business. A VERY BIG “THANK YOU” EVERYONE WHO TOOK THE TIME TO RESPOND TO MY QUESTIONS!

 

[JohnQuixote]

Date: 7/1/2007 6:51:40 PM
Author: junior35
I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It's not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has 'gletzes' coming out of it.That's another story.

Junior, I’ve heard that said.However a feather as defined by GIA - largely recognized as the global authority - is a general term for any break in a diamond. A gletz (you probably know that's a Dutch word) is a word for feather used in other countries. A feather does not need to reach the girdle. I've posted examples from GIA and AGS below. Feathers may appear at the girdle but a good rough planner can keep existing feathers away from the girdle. Also, automated bruting has virtually eliminated bearding (girdle feathering as a result of the cutting process).

One point of order:“Bubble” is not a word to use with natural diamond, since it’s a term associated with gas bubbles.These occur as separate inclusions in some synthetic or artificial materials - and in some natural ones like amber and obsidian.

Marlowe, I couldn’t agree more; this kind of exchange is why Pricescope is valued by trade members and consumers alike.

 

[Kaleigh]

Date: 7/1/2007 10:07:44 PM
Author: JohnQuixote

Date: 7/1/2007 6:51:40 PM
Author: junior35
I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It''s not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has ''gletzes'' coming out of it.That''s another story.

Junior, I’ve heard that said.However a feather as defined by GIA - largely recognized as the global authority - is a general term for any break in a diamond. A gletz (you probably know that''s a Dutch word) is a word for feather used in other countries. A feather does not need to reach the girdle. I''ve posted examples from GIA and AGS below. Feathers may appear at the girdle but a good rough planner can keep existing feathers away from the girdle. Also, automated bruting has virtually eliminated bearding (girdle feathering as a result of the cutting process).

One point of order:“Bubble” is not a word to use with natural diamond, since it’s a term associated with gas bubbles.These occur as separate inclusions in some synthetic or artificial materials - and in some natural ones like amber and obsidian.

Marlowe, I couldn’t agree more; this kind of exchange is why Pricescope is valued by trade members and consumers alike.

Excellent post Sir John!!!!

Many thanks!!

 

[Paul Cannon]

if there on the corner of a big princess
beware!

 

[junior35]

Date: 7/1/2007 10:07:44 PM
Author: JohnQuixote

Date: 7/1/2007 6:51:40 PM
Author: junior35
I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It''s not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has ''gletzes'' coming out of it.That''s another story.

Junior, I’ve heard that said.However a feather as defined by GIA - largely recognized as the global authority - is a general term for any break in a diamond. A gletz (you probably know that''s a Dutch word) is a word for feather used in other countries. A feather does not need to reach the girdle. I''ve posted examples from GIA and AGS below. Feathers may appear at the girdle but a good rough planner can keep existing feathers away from the girdle. Also, automated bruting has virtually eliminated bearding (girdle feathering as a result of the cutting process).

One point of order:“Bubble” is not a word to use with natural diamond, since it’s a term associated with gas bubbles.These occur as separate inclusions in some synthetic or artificial materials - and in some natural ones like amber and obsidian.

Marlowe, I couldn’t agree more; this kind of exchange is why Pricescope is valued by trade members and consumers alike.

Interesting,I never heard about internal feathers,but I guess there is always something new to learn,right?

 

[He Scores]

Date: 7/1/2007 7:36:20 PM
Author: strmrdr

Date: 7/1/2007 6:51:40 PM
Author: junior35

Date: 7/1/2007 1:48:14 PM
Author: snlee
A feather that doesn''t break the surface should be fine. Feather inclusions shouldn''t normally be a problem, especially if you discuss the location of feathers with your jeweler and he is aware of any potential problems. If the stone were a SI2 or I1, I would be more concerned about the potential for damage.

I have a feather reaching the girdle in my diamond and a prong was set right next to it. A prong tends to protect that area right next to it. You don''t want the prong directly over the feather because it''ll be putting pressure on it.

I think some of you are confused and Bill Bray will agree,that a feather (gletz)is normally a cleavage that comes from the girdle inwards. It''s not something internal inside a diamond.It is always open to the surface. You will on occasion have a stone where an internal bubble that has exploded and has ''gletzes'' coming out of it.That''s another story.

I don''t think Bill will agree with you because I can show you a bunch of examples to prove that''s not the case.

Storm''s correct on this one.

A feather flaw can be completely internal or open to the surface. Often times the slang term for a gletz that extends to the girdle suface is "knifey" (knife-ee).

Bill Bray
Diamond Cutter