281–290 of 511 posts
When TFA talks about semiconductors it really only directly compares it to silicon, when GaN is probably the nearest competitor to diamond, both in cost and performance. I believe diamond is "only" about 20x the cost of GaN; anyone know what the economics would be for substituting diamond for GaN in e.g. HVDC?
> A perfectly cut, flawless lab diamond costs a fraction of the price of a mined diamond of lesser quality. When I shopped for an engagement ring in 2012, there was a clear cohort of women who significantly valued a diamond from the ground. Fortunately, my (now) wife and I saw through the marketing gimmick, and laughed all the way to the bank.
Earlier quoted context omitted.
It's based on supply and demand. In 2012, when I was shopping for an engagement ring, a natural 2ct diamond cost $250,000. (I bought a 2ct moissanite for much, much less, and my wife is very happy with it.) When I looked in fall 2023, a natural 2ct diamond cost $20,000. That's a loss of over 90% of value, not counting inflation! (Now the supply of diamonds is much higher, and the demand for natural diamonds is much l…
> I also wonder if impurities will become fashionable, just to show that a specific diamond is actually natural and can't be made in a lab. I hope that happens for purely aesthetic reasons too: natural "imperfections" add a lot of visual variety and interest that's otherwise missing in a lot of diamond jewellery—at least the sort that I've seen.
Earlier quoted context omitted.
You can do that in an accelerator. It's not going to be cost-effective for a long time, though. Once we get to asteroid mining, we'll be able to get gold cheaply enough to not care about it. On Earth, most of the gold sank into the planet's core because it dissolves well in molten iron. So the gold that we're mining comes mostly from meteorites.
If you do the math on the theoretical maximum energy efficiency of turning iron into gold we'll never be able to do it cost-effectively until energy becomes cheaper by like 10 orders of magnitude. That's why heavy metals all come from the most energetic processes in the universe, like supernovae and neutron star collisions :)
That's a good article. The whole history is there. The commercial side has made huge progress, too. Look up "diamond making machine" on Alibaba. You can buy a high-pressure, high temperature six sided press for about US$200,000. A chemical vapor deposition machine is about the same price. De Beers, the diamond cartel, has an R&D operation, Element Six. They sell synthetic diamonds for lasers and other exotic applicat…
This is certainly good news for lasers. Many people don't realize how good diamonds are for this. Transparent with a 65% higher refractive index than glass, and 8x the thermal conductivity of copper. And completely scratch-proof!
Over the past 10 years, there has been an explosion in cheap lab diamond and moissanite producers in China and India. 10 years ago, it was hard to find quality lab diamonds at a reasonable price, and moissanite was still reasonably expensive at $400-600/ct. Today, given cutthroat competition and "race to the bottom" pricing strategies, lab diamonds are ubiquitous, extremely high quality, and cheap. Less than $200/ct…
"Synthetic diamonds are now purer, more beautiful, and vastly cheaper than mined diamonds. Beating nature took decades of hard graft and millions of pounds of pressure." What does graft mean in this context? Is there a process where you graft diamonds, like plants? Does it refer to the diamond seed crystals mentioned in the article?
Hard graft is an idiom. It means hard work.
Earlier quoted context omitted.
most people taking this strategy that I know use platinum instead of gold. Most engagement rings only have ~~~$200 worth of gold on them.
Did you mean rhodium?
Earlier quoted context omitted.
There is a difference in going all out for an event vs spending all that money on essentially a useless rock.
When diamonds held their value they were a useful vehicle for dowry (and showing off your dowry). Now that they don't...an Instagram account with 100K followers might be a suitable modern replacement
Over the past 10 years, there has been an explosion in cheap lab diamond and moissanite producers in China and India. 10 years ago, it was hard to find quality lab diamonds at a reasonable price, and moissanite was still reasonably expensive at $400-600/ct. Today, given cutthroat competition and "race to the bottom" pricing strategies, lab diamonds are ubiquitous, extremely high quality, and cheap. Less than $200/ct…