This thread reminds me of the Star Trek episode where Kirk & Co. are offered a bowl of gems. They are unimpressed, mentioning that they could make like a ton of them on the Enterprise.
Either deBeers hires marketing geniuses or women fall easily into marketing campaigns claims. Debeers got the world to believe a DIAMOND was THE engagement ring- whilst traditionally it was just one of several choices- including sapphires. They also gots dudes to beleive that “2 months salary” crap, and that a “diamond is a good investment” (it isn’t- at least half the price of a diamond is entirely controled by deBeers keeping loads on them off the market).
Trust you to bring it back round to Star Trek…! If it’s not Star Trek it’s Thunderbirds!! There’s just no hope for you Johnny! 
(Nice to see you though - got your place sorted fro the Cal-Mex yet? 
bump, I am really curious about this myself. If its cheap enough, good manmades could easily cripple the market regardless of advertising campaigns. Major retailers would happily pounce on less costly but otherwise difficult to distinguish from “dug outta the ground” type. Especially if technically and or chemically they are real diamonds. I didn’t ask if the diamonds in my wifes ring were dug out of the ground or manmade, but shes happy. I seriously doubt most people buying wedding rings at walmart or sears are real picky about the pedigree of their diamonds.
Sensibility, perhaps you’re not clear on this, but we’re not talking about imitation diamonds or “not-real” diamonds. Those would be things like rhinestone and cubic zirconium. We’re talking about diamonds. It’s not difficult to make diamonds with a hardness of 10, because all diamonds have that hardness. It’s not difficult to make diamonds with the same index of refraction as diamond, because they’re diamonds. A diamond is a diamond, and by definition has all of the properties of diamond.
So as a hypothetical, If DeBeers and friends built a plant producing manufactured diamonds in south africa and suddenly claims to have struck a huge vein of flawless diamonds in south africa there is zero way short of the word of the guy who dug it up and cut it that the diamonds being distributed are dug as opposed to created in the plant?
I know its a reach but if I understand this thread so far, the only real difference is whos name is on the box of a given flawless stone, dug or manufactured.
*Hi Chronos
Thanks for the Heads Up on this one. You are absolutely correct.
Addressing the OP - ‘Is a lab diamond still a diamond?’
If a substance has all the same physical and chemical properties as diamond, then classification wise, it IS diamond, yes. It just isnt a naturally occuring diamond.
*Quote: Originally Posted by Sensibility
As regards the impurities - it used to be a tell tale sign of a really good imitation diamond that it was TOO perfect. Naturally occuring diamond are seldom flawless - hence their hugely inflated value when they are
So as a hypothetical, If DeBeers and friends built a plant producing manufactured diamonds in south africa and suddenly claims to have struck a huge vein of flawless diamonds in south africa there is zero way short of the word of the guy who dug it up and cut it that the diamonds being distributed are dug as opposed to created in the plant?
I know its a reach but if I understand this thread so far, the only real difference is whos name is on the box of a given flawless stone, dug or manufactured.*
smile well perhaps not QUITE that simple, but it HAS been tried in the past!
There was a very famous instance where one of the first lab diamonds was - I think by way of an experiment? - hawked round some of the leading diamond merchants and supposedly caught one or two of them out - for a little while at least, but yes, to some extent, when talking about the discovery of something as rare as a naturally occuring ‘flawless’ diamond, or a particularly large diamond? there is a certain degree of it having to have the right history - and yes - in the beginning at least - the say so of the diamond company who ‘dug it up’ Hence their reputation stands or falls by the subsequent testing etc. Can you imagine the hullabaloo if a reputable company tried to pass a lab diaomnd off as a naturally occurring diamond?
Last but certainly not least - Oleoso
Is a lab diamond still a diamond?
I could grow salt crystals in a lab, and everyone would look and say that it’s salt. What is the difference between a diamond created in a lab and a naturally occuring stone? Leave out the part about impurities, most consumers covet flawless diamonds. I’m more interested in the molecular level and physical properties.
And here - just for you - is some technical stuff! All of which have to be matched to produce diamond.
And just one SNEEEEEKY, perhaps even picky little point if I may??
Whilst lab diamonds may match all the necessary physical and chemical properties - and therefore BE ‘diamond’ - the substance? They’re not ‘diamonds’ in the way we all tend to think of them - a naturally occuring substance. Or as **Johnny LA ** would say -
‘Its a diamond Jim, but not as we know it!’ (sorry - its been a long night…!)
(I’ll shut up now…!)
Property Value Units
Hardness 10,000 kg/mm2
Strength, tensile >1.2 GPa
Strength, compressive >110 GPa
Sound velocity 18,000 m/s
Density 3.52 g/cm3
Young’s modulus 1.22 GPa
Poisson’s ratio 0.2 Dimensionless
Thermal expansion coefficient 0.0000011 /K
Thermal conductivity 20.0 W/cm-K
Thermal shock parameter 30,000,000 W/m
Debye temperature 2,200 K
Optical index of refraction (at 591 nm) 2.41 Dimensionless
Optical transmissivity (from nm to far IR) 225 Dimensionless
Loss tangent at 40 Hz 0.0006 Dimensionless
Dielectric constant 5.7 Dimensionless
Dielectric strength 10,000,000 V/cm
Electron mobility 2,200 cm2/V-s
Hole mobility 1,600 cm2/V-s
Electron saturated velocity 27,000,000 cm/s
Hole saturated velocity 10,000,000 cm/s
Work function small and negative On [111] surface
Bandgap 5.45 eV
Resistivity 1013 - 1016 Ohm-cm
If all these are matched, then the difference is, ones naturally occurring, ones not.
So flawless artificial rubies and sapphires have been produced for ages now right? How come theres still a market for real ones?
I saw pictures of artificial rubies and sapphires and what I found weird is that they were huge. They had roughly the shape of a bullet (elongated and pointy) and you’d need both hands to hold them. They made me think of a ruby artillery shell.
By the way, I’ve been told that a lot of jewellery sold is actually using artificial rubies/sapphires/emeralds but I’ve no clue if it’s true.
But artificial rubies haven’t taken the bottom out of the natural ruby market right? So why do people expect artifical diamonds to do it?
Since I gave up hope I feel much better.
Heh, no plans on moving to London and opening a restaurant yet. Been working on the film. 
Good to see you as well.
I wouldn’t know. But on the other hand, everybody is selling/buying cultured pearls that are way cheaper than “natural” ones. So, it might happen with gemstones too.
Synthetic diamonds are diamonds. The “differences” between synthetic diamonds and mined diamonds are trivial differences. A synthetic diamond has the exact same chemical makeup as a mined diamond. It would like complaining that man-made glass isn’t really glass because it isn’t obsidian.
Synthetic diamonds are real diamonds, anyone who tries to tell you differently is selling something. Selling diamonds. Or selling the idea of diamonds, more precisely. A diamond is just a pretty rock. Nothing wrong with pretty rocks, but spending thousands of dollars for a pretty rock seems kind of dumb to me, when you can get a chemically and physically identical rock that is exactly as pretty for a fraction of the cost.
People keep dancing around the most important point here.
For industrial applications, people already use predominantly synthetic diamonds. They have the same chemical composition and same hardness as natural diamonds.
However, for cosmetic applications, synthetic diamonds have been unable to penetrate the market, because there’s one critical physical property that cannot be duplicated easily – the clear color of natural diamonds. The yellow color of diamonds comes from nitrogen which replaces carbon in the lattice – and, at least for the time being, has been pretty hard to get rid of while producing synthetic diamonds. You will not be finding clear-color synthetic diamonds in the near future, although people have billions of dollars invested in doing so.
This is false. They can be produced now, albeit at a somewhat higher cost than mining natural diamonds of similar quality. That, no doubt, will change eventually.
I don’t expect them to.
The same marketing expertise that got people to assign value to diamonds in the first place will similarly convince people of the superiority of a “real diamond” versus a “manufactured diamond”.
I saw something once on “60 Minutes” that said deBeers wanted manufactured diamonds “stamped” as such OR that they were going to stamp their mined diamonds, so that there was no confusion.
This “stamp” I think was actually some kind of etching (can you etch a diamond? whatever) that was too small to be seen with the naked eye.
Canadian Diamond mines are etching their diamonds in this way now.
Yes, the techniques uses a laser to etch microscopic serial numbers onto the girdle of the cut diamonds. The markings are invisible to the naked eye.
http://www.polarbeardiamond.com/pages/cut.html
On the top left of this page you can see the marking on a diamond.