Nanodiamonds Are Not Forever

An anonymous reader writes "Livermore Labs and the Belgian Institute of Astrophysics (Catholic University, Leuven) are reporting today that nanodiamonds trapped by U2 spyplanes are pretty common (one part per 1000 in meteors), but don't originate from violent supernovae as previously thought. Instead their absence in comets suggest they formed after our solar system (are not pre-solar) by chemical vapor deposition -- and from much less violent asteroid collisions. Their technique of spectroscopy is compared to looking for the proverbial needle in a haystack by burning down the haystack. It seems these diamond time capsules are close to perfect tracers for guessing the initial conditions when life first formed in the universe. On April 23-24, a large flux of identifiable comet dust will streak through our stratosphere from the Grigg-Skjellerup earth-crossing dust trail."

Comments

Re:"trapped"?

[jericho4.0]

IIRC, it uses a super-low density foam type material, that it simply exposes to the atmosphere when it gets really high. The assumption being, of course, that any dust and stuff captured is on its way down, not up.

And they're getting cheaper

[Animats]

Synthetic diamonds have been around for about fifty years, and most industrial diamonds are now synthetic. Synthetic gemstones were produced by General Electric in the 1950s, but you had to tie up a big press for days, which made them more expensive than natural ones. But around 1990, better processes for manufacturing diamonds were developed, and synthetic diamond gemstones are being produced in quantity. The diamond industry is trying to create the illusion that the synthetic ones are less valuable (and struggling to develop reliable tests for distinguishing them) but that may be a losing battle.

Sapphires and rubies got clobbered in the 1970s, when processes for making them were discovered. Linde Chemical introduced the "Linde Star", a perfect star sapphire, and manufactured them in volume, which killed the gem market. Today, you can buy sapphire and ruby bar stock, and it's not expensive. You can buy a 9" long x 0.125 diam. ruby rod on Ebay for $28.88 Sapphire, because it's used for semiconductors, is produced in high volume as large-diameter bar stock. When you see something like this:

• We can currently supply sapphire ingots, blanks, windows and wafers up to 200 mm in diameter, bar stock up to 100 mm square and ribbons up to 80 mm wide. All sapphire products are available in stages ranging from raw through polished for epitaxial growth. With six grades of synthetic sapphire, Maintech is sure to meet needs of the customers. Processors and end users now have an opportunity to take advantage of extraordinary prices from Maintech, Inc. Normal turnaround time is FOUR WEEKS!

you know that it's not a valuable, rare gem any more. It's more like Napoleon's rare, expensive set of aluminum dinnerware in the 1700s.

It looks like something similar is starting to happen to diamonds. Don't put your money in them.