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Da_bear
storyteller
Username: Da_bear
Post Number: 35
Registered: 5-2003
| | Posted on Tuesday, September 09, 2003 - 5:50 pm: |     |
http://abcnews.go.com/sections/GMA/SciTech/GMA0309 09Diamond_synthetics_hunter.html
Apollo Diamond Inc. in Massachusetts and Florida-based Gemesis Corp. each have produced a new type of lab-made diamond that is difficult, though not impossible, to distinguish from natural diamonds.
The companies say that their manmade gems — to be sold at lower prices than natural diamonds — will be labeled so that they will not be confused with natural diamonds. But experts say that retail jewelers would not be able to tell the difference on their own.
"No chance," said Mark Yakubov, a gemologist at the International Gemological Institute in New York. . . . . .
The new manmade diamonds from Apollo Diamond are created in a few days by a machine in an industrial park near Boston through a process called chemical vapor deposition. Diamond crystal is formed when a plasma cloud of carbon is deposited onto diamond wafers. The wafer seeds grow into diamond mini-bricks, rough diamonds that are sliced into wafers, and cut and polished into diamonds.. . . . . . . . . . .At Gemesis, which is based in Sarasota, Fla., synthetic diamonds are created through a high-pressure, high-temperature technique that mimics the geologic conditions under which natural diamonds are formed.
In a capsule placed under high temperature and pressure, graphite — a form of carbon — breaks down into atoms and travels through a metal solvent to bond to a tiny diamond seed, crystallizing layer by layer. Three or four days later, the stone that is formed is then removed from the chamber and cut and polished into a synthetic diamond.
The two companies' products are bigger, better and brighter than their synthetic predecessors. Gemesis is already selling its fancy yellow synthetic diamonds through retail jewelers at a suggested retail price of $3,250 per carat, significantly less than the price of natural yellow diamonds
The story is that they may replace silicon as the chip material of choice, due to their intense heat capacity.
The next generation of super fast chips may be diamond chips.
da bear
If you choose not to decide, you still have made a choice. |
Miisa
storyteller
Username: Miisa
Post Number: 60
Registered: 5-2003
| | Posted on Tuesday, September 09, 2003 - 6:44 pm: | |
I was under the impression that the price of diamonds was kept artificially high by De Beers (sp?) and the diamond cartel anyway, that if the market was free the prices would plummet to a fraction of what they are now.
I wonder what the implications of that would be on the markets (and not to mention on the status of diamonds), and if these manufactured diamonds could cause something like that. |
Rhi
storyteller
Username: Rhi
Post Number: 45
Registered: 5-2003
| | Posted on Wednesday, September 10, 2003 - 4:59 am: | |
I've actually been thinking of gems prices the past few days (I love watching the Exotic Gem shows on the home shopping networks  ). I absolutely hate diamonds. I think that they are only so high priced and popluar because people have been convinced that diamonds are the way to show love (especially in engagement rings), and I think it's just silly that one gem should be the symbol of love.
I agree with Miisa, that the price of diamonds is kept high by monopolies.
Why aren't other gems as expensive, if not more? Take Moldavite, a gem found only in Czech or Slovak (not sure which), that was produced by a meteorite crash on earth. That definately has a limited supply. And there's plenty of other gems that are found in limited supply, but because they aren't the big four (diamond, ruby, emerald, sapphire), they aren't as highly prized. However the big four are pretty common, while less common gems are priced lower, because they don't have the big names.
And also, how might people in Ayla's time have used gems? We have (from EC), that amber is used in jewelry, and opal is recognized as special. What about other "Pretty rocks"?
Mostly Harmless |
Miisa
storyteller
Username: Miisa
Post Number: 62
Registered: 5-2003
| | Posted on Wednesday, September 10, 2003 - 7:16 am: | |
The problem with "pretty rocks" is that many of them (including diamonds) are not very special-looking before they are cut or polished, which might be difficult in the stone age.
But I would also have expected them to have more quartz crystals and other objects/minerals that can be very pretty even without any treatment. |
Don
storyteller
Username: Don
Post Number: 82
Registered: 5-2003
| | Posted on Wednesday, September 10, 2003 - 8:49 am: | |
-------Why aren't other gems as expensive, if not more? Take Moldavite, a gem found only in Czech or Slovak (not sure which), that was produced by a meteorite crash on earth. That definately has a limited supply. And there's plenty of other gems that are found in limited supply, but because they aren't the big four (diamond, ruby, emerald, sapphire), they aren't as highly prized. However the big four are pretty common, while less common gems are priced lower, because they don't have the big names. ------
Diamond is the premier stone, and always will be, because it sparkles like no other. Moldavite has less sparkle than even quartz, and less than some glasses, and has a hardness of only 5.5.
This hardness is less than quartz at 7, sapphire at 9, and 10 for diamond. The only thing Moldavite has going for it is that it is rare.
Hardness of a stone will determine how well it stands up to daily use on the finger. Moldavite would scratch and become dull very quickly. Sapphire is pretty good, but not as good as diamond.
My white gold wedding ring has two sapphires, a large blue and a smaller white. The white is very rare, but almost valueless except to me, to whom it is without price, since it was in my mother's engagement ring.
The reason it is of little value though rare, is that it has little sparkle. Coloured sapphires have value because of their colour, but not their sparkle.
My father spent a weeks wages on a tobacco tin of "gravel" from a miner in the emerald/sapphire district of Queensland, when he was a station hand (cowboy) there.
The gravel consisted of a wide range of zircons, garnets, and sapphires. He had them cut by a jeweller friend of his.
Sparkle is determined by the refractive index of the stone, which measures how much light is bent when passing from the air to the stone.
Below is a list of the refractive index of various minerals. The greater the index, the better the stone for gems.
Plastic................1.46-1.70
Glass..................1.44-1.90
Moldavite..............1.50
Quartz.................1.55
Emerald................1.576-1.582
Topaz (white)..........1.63
Andradite..garnet......1.82-1.89
Ruby...................1.76-1.77
Sapphire...............1.76-1.77
YAG....................1.83 (this is a synthetic diamond-like stone)
Diamond................2.417-2.419
Don
(Message edited by don on September 10, 2003)
take what you want and pay for it |
Thalion
storyteller
Username: Thalion
Post Number: 201
Registered: 5-2003
| | Posted on Wednesday, September 10, 2003 - 10:59 am: | |
Oh- I would love to have a tin full of that gravel...
I love all pretty stones, but don't own much jewelry apart from a necklace with an opal.
I think, apart from hardness and sparkle, the value for the stones also comes from their history, and the sometimes esoteric characterizations they were attributed with. Didn't the Egyptians use Lapislazuli for some special reason? And aren't rubies used by bishops for some reason? Would have to look up the details, but some of you might know..
I love deadlines. I like the whooshing sound they make as they pass by - Douglas Adams |
(Unregistered Guest)
visitor
| | Posted on Wednesday, September 10, 2003 - 3:53 pm: | |
Don, is YAG like cubic zirconia? Or something else altogether? |
Don
storyteller
Username: Don
Post Number: 83
Registered: 5-2003
| | Posted on Thursday, September 11, 2003 - 1:24 am: | |
From:
http://www.jewellerycatalogue.co.uk/diamonds/simul ants.htm
YAG: Yttroaluminate Y3Al5O12; (not related to garnet); Cubic symmetry; Relative Density: 4.57-6.69 heavy; Small Dispersion:0.028; Refractive Index: 1.83; Good Hardness:8.5; Grown by flux melt method and used widely in the early 1970's to be replaced later by Cubic Zirconia.
This was first marketed in 1969, being made famous when Richard Burton had a copy of a 69 carat pear shaped diamond given to his wife, Elizabeth Taylor, made in YAG. It is quite hard, loups clean, and is singly refractive like diamond. It has less fire than diamond, but when cut with slightly different facet angles, starts to approach a good diamond look-a-like. These newly cut stones were marketed under the name 'Diamonaire'. It is relatively hard and holds a good polish with an adamantine lustre. It has a high relative density, and when weighed is clearly too heavy for an equivalent cut in diamond. A 1.00 carat stone measured on a Moe's gauge would weigh around 1.30cts on a balance. An immersion test in refractive liquids, will reveal its lower refractive index.
CZ
Cubic Zirconia: Zr02 mixed with Yttrium Oxide (Y203) or Calcium Oxide (CaO) as a stabilizing agent. Refractive Index:2.16; Relative Density:6; Dispersion:0.060; Hardness: 8.5. Introduced in 1977, the similarity with the figures for diamond make this the second best simulant produced to date, second only to a new type of stone called Moissanite
Cubic Zirconia is an artificial synthetic because the stabilizing oxides used in its manufacture remain in the finished product and its structure is different to the natural material Baddeleyite Zr02. This has been such a good imitation that cubic zirconia can be purchased in both graded colours and clarities. Its refractive index is near enough for the stone to remain quite brilliant when tilted, and although the dispersion is higher than that of diamond, is not so obvious to the layman, and close enough to deceive. The relative density is much higher than diamond and a loose stone will appear to weigh too much. If set, it is easy to destructively test the stone with a diamond hardness pen.
Moissanite
Moissanite is a new product but its origins go back to 1893 when Dr. Henri Moissan, a French chemist and later a Nobel Prize winner, identified minute quantities of natural silicon carbide, known as lusenite, in the Diablo Canyon meteorite found in a remote area of Arizona. Recently, these elements were replicated in a synthetic material to produce a synthetic gemstone with similar properties to diamond. The gemstone is more brilliant than diamond, Refractive Index 2.65-2.69, has a higher lustre than diamond at 20.4%, and a hardness of 9.25 , diamond being 10. Relative Density: 3.21. Because moissanite replicates a diamond so well, it could be sold as a diamond to the unwary buyer
take what you want and pay for it |
Roon
bear cub
Username: Roon
Post Number: 9
Registered: 9-2003
| | Posted on Thursday, September 11, 2003 - 3:45 am: | |
Thanks very much, Don. I realized I forgot to sign in when I posted that- it was me.
Never offend people with style when you can offend them with substance~ Sam Brown |
Rhi
storyteller
Username: Rhi
Post Number: 46
Registered: 5-2003
| | Posted on Saturday, September 13, 2003 - 10:59 pm: | |
Thanks for the sparkle numbers, Don. I know a lot about the hardness of stones, but not as much about the sparkle (except that diamond was highest).
I guess I'm just weird. For me, it's not about sparkle or hardness, it's about uniqueness, or an interesting cut.
I'm sure there were stones (not necessarily gems) that people found interesting in Ayla's time. Geez, Ayla's found enough interesting things for her amulet all by herself.
(I don't think I'm making much sense right now, I haven't been able to sleep in two days)
Well, I'm not fond of artificial stones. I'd rather have an affordable garnet or amethyst than a big fake diamond (even if it was yellow  ).
Mostly Harmless |
Darsina
bear cub
Username: Darsina
Post Number: 21
Registered: 9-2003
| | Posted on Sunday, September 14, 2003 - 7:42 pm: | |
Originally posted by Thalion:
Didn't the Egyptians use Lapislazuli for some special reason?
You’re right, Thalion. The ancient Egyptians used Lapislazuli to carve scarabei figures or scarabei pendulums. The scarabeus, also known as pill-bug, was the morning sun-god Chepri that made the sun disc move over the eastern horizon. Therefore the small figurine was a symbol for divine creation. |
Thalion
storyteller
Username: Thalion
Post Number: 243
Registered: 5-2003
| | Posted on Friday, September 19, 2003 - 2:46 pm: | |
Aha! Thank you, Darsina. Do you have an idea what Lapis Lazuli stood/stands for? Divine Creation like the figurine? Or the heavens? Sky and sun?
Diamonds, I think, represent consistency. That's why they are often used with gold for engagement and wedding rings, isn't it? Gold also represents that, I think, and also fidelity.
I love deadlines. I like the whooshing sound they make as they pass by - Douglas Adams |
Darsina
bear cub
Username: Darsina
Post Number: 37
Registered: 9-2003
| | Posted on Friday, September 19, 2003 - 8:11 pm: | |
The mineral Lapis Lazuli indeed represented the sky, but also water, especially the deep blue ocean. On a more abstract level it embodied divine powers that give life. Together with gold, the colour of sun-god Ra, it displays the starry sky and Ra’s omnipotence or the universe. Thus blue and gold were the colours worn by Ra’s sons, the Pharaohs. A good example for the combination of blue and gold is Tutankhamen’s death mask.
Colours in Ancient Egypt
Picture of Tutankhamen’s death mask
I’d also say that diamond stands for consistency, since it can only be destroyed by fires of great heat (requires supply of pure oxygen). Therefore it’s also a symbol for the 60th wedding anniversary. A marriage that has lasted for at least 60 years is considered to have become indestructible. I know there’s no rule without exception, especially in modern days society, but IMO there’s much truth in this saying. |
Darsina
bear cub
Username: Darsina
Post Number: 38
Registered: 9-2003
| | Posted on Friday, September 19, 2003 - 8:22 pm: | |
Originally posted by Da_bear:
The story is that they may replace silicon as the chip material of choice, due to their intense heat capacity.
My professor in physical chemistry always said that he'd love having the Cullinan to run an experiment on conductivity.  |
Frebec
bear cub
Username: Frebec
Post Number: 12
Registered: 6-2004
| | Posted on Monday, June 28, 2004 - 6:32 pm: | |
The information given was from a show on Diamonds that I saw. I think Discovery or The Learning Channel. DeBeers does own 80% of the market it stated but they talked about new mines that are being opened up in of all places Canada's frozen north.
As for price I do believe that Alexandrite is more expensive. ($10,000 a carat) Of course that depends on the stone.
Fake diamond production has improved over the years from the first ones done. Little diamonds with lots of pressure. But everything does get better as you go along. |
Extremed
bear cub
Username: Extremed
Post Number: 1
Registered: 8-2005
| | Posted on Monday, August 29, 2005 - 10:16 pm: | |
Hi,
I found some useful information on Celebrity Chique
You can also check the Celebrity Chique Accesories page, there are many jewlery at prices you can afford. |
Scott
flint knapper
Username: Scott
Post Number: 1040
Registered: 5-2003
| | Posted on Tuesday, August 30, 2005 - 2:08 am: | |
Yes Frebec, we have "polar bear" diamonds. My wife has one - but not in her wedding ring. She has panned gold from BC for that.
They are mined in Canada, cut and crafted here as well. DeBeers can rot.
Scott
~ ~ ~ ~ ~ ~ ~ ~
Ces gens, Jondalar, ils sourient. Ils me sourient. - Ayla |
Da_bear
flint knapper
Username: Da_bear
Post Number: 710
Registered: 5-2003
| | Posted on Wednesday, August 31, 2005 - 5:43 pm: | |
http://www.newscientist.com/article.ns?id=dn7926
Nano-material is harder than diamonds
18:18 30 August 2005
NewScientist.com news service
Will Knight
Facility
Applied Physics Letters
A material that is harder than diamond has been created in the lab, by packing together tiny "nanorods" of carbon.
The new material, known as aggregated carbon nanorods (ACNR), was created by compressing and heating super-strong carbon molecules called buckyballs or carbon-60. These molecules consist of 60 atoms that interlock in hexagonal or pentagonal shapes and resemble tiny soccer balls.
The super-tough ACNR was created by compressing carbon-60 to 200 times normal atmospheric pressure, while simultaneously heating it to 2226°C.
The properties of the resulting material were then measured using a diamond anvil cell at the European Synchrotron Radiation Facility in France. This instrument squeezes a material between two normal diamonds, enabling researchers to study it at high pressure using synchrotron radiation – extremely intense X-rays which reveal the material’s structure.
The researchers found their ACNR to be 0.3% denser than ordinary diamond and more resistant to pressure than any other known material.
Industrial applications
"Our material actually scratches normal diamonds," says Natalia Dubrovinskaia, of the University of Bayreuth, in Germany, who led the research. "We were very excited, and glad."
While an ordinary diamond gets its hardness from the strong molecular bonds between each of its atoms, ACNR derives its strength from the fact that it is formed from interlocking nanorods, the researchers say.
Dubrovinskaia told New Scientist the material could have a wide range of potential industrial applications. As it is stable at very high temperatures, she says it could be better than normal diamond for deep drilling and polishing abrasive materials. She also believes it will be easy to mass produce the super-tough material. "It's a very reproducible result," she adds.
Journal reference: Applied Physics Letters (vol 87, 08, p 3106)
A new style of diamonds.
If you choose not to decide, you still have made a choice. |
Magchielisnikolaas
bear cub
Username: Magchielisnikolaas
Post Number: 49
Registered: 7-2005
| | Posted on Thursday, September 01, 2005 - 5:51 am: | |
I heard from my professor phisics that there diamond producents made 'faults' in artifficial diamonds, because natural diamonds have them too. Anyone knows if that's true? |
Frebec
gatherer
Username: Frebec
Post Number: 89
Registered: 6-2004
| | Posted on Saturday, September 03, 2005 - 3:32 pm: | |
I wonder why someone would want a fault in a diamond fake or not. Price for one I could understand as to get a "Gem Class" quality stone would cost you much. But the only thing I could understand to do that with a fake is to get maybe a real life look to it.
Fake diamonds can be seen differently under a certain type of light. I don't have that information handy at this point and wonder if they are not trying to correct that part of the problem. If they do get that fixed than I would think that maybe that could drive the price of diamonds down being afraid is it real or a fake?
When you have a bad day put a little Yang-Guang into your life. |
Cavebear
cave painter
Username: Cavebear
Post Number: 2246
Registered: 9-2003
| | Posted on Sunday, September 04, 2005 - 12:12 am: | |
I can't help but wonder why "2,226 C" and not just 2,225 or 2,227? It seems oddly precise. Is that like the freezing or boiling point of water (at standard pressure)?
Machiavelli was pretty devious. For a guy... |
Da_bear
flint knapper
Username: Da_bear
Post Number: 725
Registered: 5-2003
| | Posted on Sunday, September 04, 2005 - 5:42 pm: | |
I would suspect, but do not know, the temperature reflects the exact point where atoms will migrate under the pressure, but not be volatile to such a point where the desired shape is not formed.
That point would be a rather precise one, IMO, but I cannot give any reason but "it seems so".
I know in cooking, a tiny change in the temperature of some candies will dramatically effect the final crystalline texture and flavor.
da bear
If you choose not to decide, you still have made a choice. |
carebearqueen (Unregistered Guest)
visitor
| | Posted on Tuesday, June 10, 2008 - 3:38 am: | |
hi i was wondering how much a 9.00mm round pink tourmaline or garnet or topaz would weight in carats.
thanks,
carebearqueen |
Don
flint knapper
Username: Don
Post Number: 1226
Registered: 5-2003
| | Posted on Tuesday, June 10, 2008 - 11:45 am: | |
The volume of a sphere is 4/3 times pi times radius cubed.
A one centimetre cube of water weighs one gram at four degrees celsius.
To get carats from grams, multiply by five.
The specific gravities (averaged) of the stones you mention are:
tourmaline 3.14
garnet 3.9 (highly variable, garnet has unknowns in its chemical formula)
topaz 3.54
(that is, tourmaline is 3.14 times as heavy as water, and so on)
Which gives, for what it's worth, all care and no responsibility:
tourmaline 5.99
garnet 7.44
topaz 6.76
So call the tourmaline 6 carats, the garnet 7.4 carats, and the topaz 6.8 carats.
Unless I've misplaced a decimal point somewhere, of course.
It's been a long day, others feel free to point out the deliberate mistake....
take what you want and pay for it |
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