* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Home -> Astronomy News -> Meteorite News -> Carbonado diamonds
Post Info TOPIC: Carbonado diamonds
Blobrana


L

Posts: 131433
Date:
RE: Carbonado diamonds
Permalink  
 

What is a black diamond?

"There are distinctions among black diamonds. There are the so-called true black diamonds, which are diamonds in every sense of the word, except that they're black. These are largely but not exclusively from the Urals in the former Soviet Union, in Russia. The second type are carbonado, which are not known apart from two localities on Earth, namely Bahia in Brazil and the Central African Republic. I ought to add that there's been over 600 tons of diamonds that have been mined, polished, cut, traded, stolen, and embellished on various body parts since about 1900. But not a single carbonado has been found in any of those mines. So there are these two spots on Earth, the Central African Republic and Bahia in Brazil, and at one point in time those two continents were joined. Geologically and geographically that's one piece of real estate. And that's the one place on Earth where carbonado is found" - Dr. Stephen E. Haggerty, a South African born geophysicist and Fulbright scholar who currently teaches at Florida International University 

Source



__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Two new ultra-hard types of diamonds were found in a meteorite from Finland, Discovery News reported.
The ultra-hard carbon crystals were discovered in the Havero meteorite, which fell to Earth in 1971.
Read more

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Super Hard Diamonds Found in Meteorite

Researchers using a diamond paste to polish a slice of meteorite stumbled onto something remarkable: crystals in the rock that are harder than diamonds.
A closer look with an array of instruments revealed two totally new kinds of naturally occurring carbon, which are harder than the diamonds formed inside the Earth.
The researchers were polishing a slice of the carbon-rich Havero meteorite that fell to Earth in Finland in 1971. When they then studied the polished surface they discovered carbon-loaded spots that were raised well above the rest of the surface - suggesting that these areas were harder than the diamonds used in the polishing paste.
Read more

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Carbonado, commonly known as the "Black Diamond", is a natural polycrystalline diamond found in alluvial deposits in the Central African Republic and Brazil. Its natural colour is black or dark grey, and it is more porous than other diamonds.
Read more

__________________
Blobrana


L

Posts: 131433
Date:
Black diamonds
Permalink  
 

Rare black diamonds may have come from space

Black diamonds found in only a few places on Earth may have crashed down from space in a kilometre-sized rock, according to new research.
The diamonds, also called carbonado, are only found in Brazil and the Central African Republic. Unlike other diamonds, they are made of millions of diamond crystals that are stuck together.
Read more

__________________
Blobrana


L

Posts: 131433
Date:
Cosmic diamonds
Permalink  
 

An exotic carbon structure could explain why astronomers have seen very little diamond dust in the universe.
Since the 1980s, researchers have puzzled over the origin of "nanodiamonds", tiny diamond deposits preserved in meteorites, such as the Allende meteorite that landed in Mexico in 1969.
These tiny diamonds make up roughly 3% of the carbon in the rocks. That suggests nanodiamonds should abound in clouds of interstellar gas and dust, possibly forged in the fiery blasts of previous supernovae.
But so far, signs of diamonds have only been found in the dusty discs around three young stars. Strangely, the diamonds are found close to the stars, as opposed to being distributed more evenly in the space around them. That hints that they were not left over from ancient stellar explosions but may have formed near the stars, at comparatively low pressures.
Now researchers led by Miwa Goto of the Max Planck Institute for Astronomy in Heidelberg, Germany, say they have come up with an explanation.
Nanodiamonds may be hidden from view in many places because they form within "carbon onions", exotic structures made up of concentric layers of graphite that can form in dusty material that is blasted with high-energy particles, the researchers say.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
Nanodiamonds.
Permalink  
 

Diamonds may be rare on Earth, but surprisingly common in space -- and the super-sensitive infrared eyes of NASA's Spitzer Space Telescope are perfect for scouting them, say scientists at the NASA Ames Research Centre in Moffett Field, California.
Using computer simulations, researchers have developed a strategy for finding diamonds in space that are only a nanometer (a billionth of a meter) in size. These gems are about 25,000 times smaller than a grain of sand, much too small for an engagement ring. But astronomers believe that these tiny particles could provide valuable insights into how carbon-rich molecules, the basis of life on Earth, develop in the cosmos.
Scientists began to seriously ponder the presence of diamonds in space in the l980s, when studies of meteorites that crashed into Earth revealed lots of tiny nanometer-sized diamonds. Astronomers determined that 3 percent of all carbon found in meteorites came in the form of nanodiamonds. If meteorites are a reflection of the dust content in outer space, calculations show that just a gram of dust and gas in a cosmic cloud could contain as many as 10,000 trillion nanodiamonds.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
Carbonado diamonds
Permalink  
 

If indeed "a diamond is forever," the most primitive origins of Earth's so-called black diamonds were in deep, universal time, geologists have discovered. Black diamonds came from none other than interstellar space.
In a paper published online on December 20, 2006, in the journal Astrophysical Journal Letters, scientists Jozsef Garai and Stephen Haggerty of Florida International University, along with Case Western Reserve University researchers Sandeep Rekhi and Mark Chance, claim an extraterrestrial origin for the unique black diamonds, also called carbonado diamonds.
Infrared synchrotron radiation at Brookhaven National Laboratory was used to discover the diamonds' source.

"Trace elements critical to an 'ET' origin are nitrogen and hydrogen" - Stephen Haggerty.

The presence of hydrogen in the carbonado diamonds indicates an origin in a hydrogen-rich interstellar space, he and colleagues believe.

Read more

Attachments
__________________
Page 1 of 1  sorted by
Quick Reply

Please log in to post quick replies.
Home -> Astronomy News -> Meteorite News -> Carbonado diamonds


Create your own FREE Forum
Report Abuse 		Powered by ActiveBoard