Diamond cutting

I think it was a Lincoln comm’l to demo it’s smooth ride ( I think).

In any case as I understand the process, it’s the study of the rough
that takes time and expertise. Once a decision is made as to where
the rough should be cleaved the rough is then notched and struck with
the appropriate tool to cleave the material.

The irony of the comm’l is that a chimp could have accomplished what
was shown in the comm’l. All the difficult work was done before that
blow was struck.

Kevin

There's a story of one of the really big diamonds and the diamond
cutter studying it for months, finally deciding and then he
cleaves it, successfully, then faints.  Don't know if it's true,
but it's a good story.

Source:
http://www.original-diamonds.com/famous_great_africa.php

  530.20 Carats - the Cullinan I or Star Africa diamond is the
  largest cut diamond in the world. Pear shaped, with 74 facets,
  it is set in the Royal Scepter (kept with the other Crown
  Jewels in the Tower of London). 

  It was cut from the 3,106-carat Cullian, the largest diamond
  crystal ever found. The Cullian was discovered in Transvaal,
  South Africa in l095 on an inspection tour of the Premier Mine. 

  The Cullian was cut by Joseph Asscher and Company of
  Amsterdam, who examined the enormous crystal for around six
  months before determining how to divide it. It eventually
  yeilded nine major, and 96 smaller brilliant cut stones. When
  the Cullian was first discovered, certain signs suggested that
  it may have been part of a much larger crystal. But no
  discovery of the "missing half" has ever been authenticated. .. 

I remember reading in “Diamonds a Journey to Obsession” that Joseph
Asscher had a doctor and nurse standing by when he cleaved the rough
stone and fainted after he struck it.

Rick Copeland
Silversmith and Lapidary Artisan
Colorado Springs, Colorado
http://home.covad.net/~rcopeland/

    There's a story of one of the really big diamonds and the
diamond cutter studying it for months, finally deciding and then he
cleaves it, successfully, then faints.  Don't know if it's true,
but it's a good story. " 

Elaine, It’s a true story except that he fainted first. He managed
to cleave it on the second go. I believe it was one of the english
crown jewels.

Eileen

Hi,

It was the Cullinan diamond. I read somewhere that only half the
original crystal was recovered from the quarry wall. Half the diamond
may have been destroyed by the mining operation! What was left has
certainly resulted in 9 very large stones! You can visit the stone in
London at the Tower.

This link has a bit of diamondtutorials.com

  The Cullinan Diamond

   diamondtutorials.com/famousdiamonds/roughcullinan.jpg

         Weight: 3,106 carat (rough)
         Cut: Final cut Pear shaped diamond

  This 3,106 carat diamond is the largest gem diamond ever
  found. It was discovered in 1905 at the Premier mines in South
  Africa by Frederick Wells, a mine superintendent. He was
  walking through the mine at the end of the day, when he
  happened to glance up. He noticed a large mass in one side of
  the mine wall. Thinking it was a big piece of glass embedded
  by a practical joker he examined what turned out to be a huge
  diamond. Wells received $10,000 for his find. The diamond was
  named Cullinan, after the mine's owner Sir Thomas Cullinan. 

  It was purchased for $800,000 as a present for King Edward VII
  for his 66th birthday. The stone was sent to the Asscher
  Brothers in Amsterdam to be cut. They had successfully cut the
  Excelsior, previously the largest diamond. The huge uncut
  stone was studied for months. Then on February 10, 1908, Mr.
  Asscher stuck the steel cleaver's blade to make the first cut.
  The blade broke while the diamond remained intact. 

  On the second attempt, it split exactly as planned. It was
  reported that after the second cut, Mr. Asscher fainted.
  Further cuts produced three principal parts, and these in tern
  were cut into 9 major gems, 96 smaller brilliants, and 9.5
  carats of unpolished pieces.The Cullinan I was the largest gem
  produced from the rough stone. It is a pear shaped stone of
  530.2 carats and is the world's largest cut diamond. 

  The Cullinan I is now in the head of the royal scepter in the
  British crown jewels. The second largest cut diamond, the
  Cullinan II, is a cushion-shaped stone weighing 317.4 carats,
  and is set in the British imperial state crown. 

Karen in Toronto - where winter refuses to end - sigh

I think the diamond in question must have been the Kohinoor.
Pat

Kohinoor = A famous diamond, surrendered to the British crown on the
annexation of the Punjab. According to Hindoo legends, it was found
in a Golconda mine, and has been the property of various Hindoo and
Persian rulers.

Pat,

   I think the diamond in question must have been the Kohinoor. 

No, it was the Cullinan, not the Kohinoor. Another post on this
thread did a great job of describing the history of the Cullinan…
The legend of Mr. Asscher fainting, before or after the cleaving,
however, may be just that, a legend. I remember reading in one of the
industry publications not to long ago,( JCK maybe?) of an interview
with Mr Asscher’s son regarding the event. He said the fainting story
was not true at all, but that his father did the job as a matter of
course and described the event to the family that evening over
supper. Hype has always been with us, eh?

Jerry in Kodiak

Hype has always been with us, eh? 

Especially where diamonds are concerned!

Dave

Hello all,

I actually have a diamond cleaver,and I have used it a few times.

Twice I used the diamond cleaver, when I needed to make a cut on a
beautiful amazonite, by cleaving (feldspar); there was a small
developed crack, I needed to relieve the existing stress, and no,
none of my 9 diamond saws woudl work.

the last time, I used the cleaver on a 35 ct topoaz, again to get a
cut just so, and relieve the stress on a crack.

Oh,almost forgot - I had an otherwise uncuttable virgin valley,
nevada opal, with a crack very near (0.0025", yes,correct # of
decimal places) the color plane. used the cleaver, it is now one of
the finest pure brilliant red flash stones I own.

So, another tool in the bench,even If I only use it every 2nd year.

Mark Zirinsky,Denver
Sincerely,

Mark Zirinsky
PEMED
6035 E 38th Avenue
Denver, Colorado 80207
USA
1-303-393-7800
1-303-393-7400
1-303-393-1482 (fax)

http://www.surgicaltable.com
http://www.used-medical-supply.com
@Mark_Zirinsky
markzy@covad.net

     So, another tool in the bench, even If I only use it every 2nd
year. 

Mark–

How did you learn how to use your diamond cleaver successfully?

Noel