Golconda diamond?????????????

[windowshopper]

anyone know anything about this cut--? i believe its a variation of an Emerald cut. I''ve seen Golconda and Golconda type IIa or something like that.

 

[valeria101]

Date: 1/9/2005 12:55:24 AM
Author:windowshopper
anyone know anything about this cut--? i believe its a variation of an Emerald cut. I''ve seen Golconda and Golconda type IIa or something like that.

If this is the name of a cut, then it is something new... usually "Golconda diamonds" means about the same as "Kashmir sapphire" - a type of material, not a cut.

Does the word appear in some context implying it describes a cut model ?

 

[windowshopper]

yes-i knew it was also the name of a mine but i saw a diamond ring in a nelson rarities catalogue and it was described as " antique emerald cut type 2 golconda"

 

[valeria101]

Oh... I guess it does have the usual meaning - type 2 diamond crystal which is associated with "Golconda" - the hystoric name.

I am not sure if the origin of diamonds is determined as it is done for sapphire or other gems. Type 2 diamonds come from all over, not just the old specimens qualify. But both type 2 and Golconda sounds like great pedigree - and are sometimes mentioned side by side.

I only know this as the name of a mine (or mining district, or whatever - since the mine is not known).

 

[windowshopper]

oh so its characteristics of the crystal not the cut itself? i didnt receive that pm for some reason...

 

[valeria101]

Date: 1/9/2005 1:12:28 AM
Author: windowshopper
oh so its characteristics of the crystal not the cut itself? i didnt receive that pm for some reason...

I think so. Otherwise there woundn''t be "Golconda" briolettes out there or what not...

Here''s a cute thing: the type IIa is the one suitable for HPHT, so there is a special tester for it (link).

About PM: the attachment was rather large. It may take a bit... sending a smaller one anyway.

 

[cflutist]

The city of Golconda, an ancient diamond-cutting center, was also the nucleus of a separate nation before its unification with India. The fortress of Golconda still stands, five miles west of the modern city of Hyderabad.

Travernier visited a number of mines between 1630 and 1668, and most of our knowledge about them comes from his writings. The most famous workings were at Kollur in the great gorge cut by the river Krishna in the south of the former kindgom of Golconda, now part of the State of Hyderabad. Kollur was where several historical diamonds, including the Koh-I-Noor, the Regent, the Great Mogul, and the Tavernier Bluer were found.

Golconda is also an old trade term once used to describe exceptionally transparent, colorless diamonds.

 

[windowshopper]

thanks cflutist!

 

[RockDoc]

My knowledge of this is somewhat limited.

I know a little, but what I can tell you is this type of stone is very rare, and only exists in "old pieces".

Those that do have them know what they are, and basically the only market where they are sold is the major auctions.

They are supposedly a better and more transparent, colorless diamond than even the "D" color.

I haven''t seen one....so can''t give personal experience with them.

Dave Atlas may know as he deals with used jewelry...maybe he''s had some personal experience with them.


Rockdoc

 

[tonysgeko]

There''s a pic of one here donaldhaack .

 

[chantal990]

I haven''t been able to find anything that refers to it as a cut. I also have heard of it as an qualifier for a stome as in kashmir sapphire and burmese ruby etc etc etc but I was never really sure what people were talking about and now I know

I like knowing things. And that''s a great picture by the way. Thanks window shopper for starting this topic

 

[Garry H (Cut Nut)]

Date: 1/9/2005 1:31:14 AM
Author: cflutist
The city of Golconda, an ancient diamond-cutting center, was also the nucleus of a separate nation before its unification with India. The fortress of Golconda still stands, five miles west of the modern city of Hyderabad.

Travernier visited a number of mines between 1630 and 1668, and most of our knowledge about them comes from his writings. The most famous workings were at Kollur in the great gorge cut by the river Krishna in the south of the former kindgom of Golconda, now part of the State of Hyderabad. Kollur was where several historical diamonds, including the Koh-I-Noor, the Regent, the Great Mogul, and the Tavernier Bluer were found.

Golconda is also an old trade term once used to describe exceptionally transparent, colorless diamonds.

Our Flute player (Flortist??? spelling??) is on the money.
Golconda diamonds were often type !! which are the purest type and grow to large stones very quickly. There were also many very famous colored diamonds.
The mining was alluvial and recently companies have begun to search for the original pipe (which may have been completely eroded away).

Australia and India were once joined - Argyle and Golconda would have been very close to each other and since many Argyle diamonds are also type II it is likely they came from the same primary source. Unfortunately the Argyle Lamproite 9not Kimberlite) pipe probably stopped 1/2 way up and allowed the diamonds to be etched away and subjected to stress which caused them to become champagne brownish. Much of the HPHT colorless diamonds like GE LK Belataire come from Argyle rough.

 

[AGBF]

I saw, "Golconda" and jumped! I have been fascinated by the story of colorless Golconda diamonds for years and would love at least to see one if I can never own one! Once I searched the ''net looking for one just to *see* its price...but I never found one for sale!

Deborah

 

[valeria101]

Garry, is "Golconda" something testable (type IIa, high D color, faint pink) or a cultural label ?

I thought "all of the bove"...

 

[Garry H (Cut Nut)]

Date: 1/9/2005 11:40:57 PM
Author: tonysgeko
There''s a pic of one here donaldhaack .

This one is for sale.

But I really do not know if there are any tests to verify Golconda origin - I do not know if they are all type II - and type II come from other sources.

If you know the diamond is more than 500 years old then there is a good chance - but that is not known about diamonds unless they have been in Royal families and renown collections.

But i will be in India in a month or so on the Palace Train tour visiting Mogul paalaces etc - I will ask around.

 

[mdx]

The tobacco tycoon RJ Reynolds purchased a 30ct Emerald Cut Golconda back in the sixties

Johan

 

[valeria101]

Date: 1/10/2005 4:34:42 AM
Author: Garry H (Cut Nut)

But i will be in India in a month or so on the Palace Train tour visiting Mogul paalaces etc - I will ask around.

Some field work, Garry !

 

[windowshopper]

Date: 1/10/2005 12:53:18 AM
Author: Emeraldgirl
I haven''t been able to find anything that refers to it as a cut. I also have heard of it as an qualifier for a stome as in kashmir sapphire and burmese ruby etc etc etc but I was never really sure what people were talking about and now I know

I like knowing things. And that''s a great picture by the way. Thanks window shopper for starting this topic

i love all this stuff..............................!

 

[AGBF]

Garry,

On another note (and anyone else should feel free to jump in here, too!), your posting made me think of something I had not thought of before.

If one cannot verify a colorless diamond as a Golconda, there have to be other colorless stones out there. (Type II or not!)

I know that no LAB will currently label a stone as higher in color than a "D", but can one find a colorless stone? (I mean, if one could not, it would be easy to verify that a colorless stone was a Golconda!) Have you ever seen one that made a "D" in a master set look faintly yellow? Has any other gemologist who has seen a lot of stones? Dave (oldminer)? Rockdoc? Any of the Richards?



Deborah

 

[windowshopper]

Date: 1/10/2005 11:59:49 AM
Author: AGBF
Garry,

On another note (and anyone else should feel free to jump in here, too!), your posting made me think of something I had not thought of before.

If one cannot verify a colorless diamond as a Golconda, there have to be other colorless stones out there. (Type II or not!)

I know that no LAB will currently label a stone as higher in color than a ''D'', but can one find a colorless stone? (I mean, if one could not, it would be easy to verify that a colorless stone was a Golconda!) Have you ever seen one that made a ''D'' in a master set look faintly yellow? Has any other gemologist who has seen a lot of stones? Dave (oldminer)? Rockdoc? Any of the Richards?



Deborah

interesting question?? how does the gemologist test for the "absolute absence of nitrogen?" would that be the determining factor?

 

[valeria101]

No idea what this no-N-purity means. Color is also made by crstal structure not chemistry (pink and brown, no ?) and if you look deep enough, some of these famous stones were reputed "faint pink" not whiter than white.

D is a very narrow range already, but take Fred Quellar''s word for it, and he''d sell you super white diamonds by the dozen. You can ask him how he IDs these too

The identification of type II diamonds became interesting since these can be bleached (HPHT). The type was more readily identifyiable than the treatment itself, so there is a device to do just that - pick type II diamodns from the pile regardless of their color grade. (mentioned on the previous post on this page).

Historic diamonds are very special treasures, of course. But I don''t think the G-name stands for anything a gemologist that is not a historian can tell. Not just my jaded idea, Richard Wise has a page on this HERE. I love, love that piece of writing - as much as the traditional grading it teaches. The dead on paragraph is this:

Do ultra-transparent Indian diamonds really exist?
Benjamin Zucker believes so, “Place a Golconda diamond”, he suggests, “along side a modern, recently cut D-colour diamond and the purity of the Golconda stone will become evident.”

Mary Murphy Hammid in a essay on Golconda diamonds written for Christie’s maintains: “I’ve seen the incredible transparency that people say is characteristic of Golconda diamonds in stones the GIA graded G and H,”. And why not? crystal (or diaphaneity - by a modern word n.r.) and color are two distinct qualities. Super-d(iaphaneity) is an obvious misnomer. These diamonds are not ultra-white, they are ultra-transparent.

Colored diamond expert Stephen Hofer speculates that the quality of ultra transparency may be the result of a quiescent geological environment on the Deccan Plateau that allowed for the development of a particularly well-formed diamond crystal lattice. >>

IMO, the four expert opinions cited side by side show just how obscure this topic is.

 

[windowshopper]

wow..................thanks.

 

[fuffi]

The Idol''s Eye is believed to be a Golconda diamond and is referred to as ''a blue-white color typical of the source''. Anyone interested in reading the history of some famous diamonds and colored gems should check out famousdiamonds.tripod.com. There is wealth of fascinating info on there.