Tag Archives: diamonds

The world’s largest jeweler goes all-synthetic on diamonds

Pandora, the world’s largest jeweler, announced that it will no longer sell natural, mined diamonds, switching exclusively to stones manufactured in the lab.

Alexander Lacik, Pandora’s chief executive, explained for the BBC that the company’s shift is part of their broader efforts towards sustainability. Concerns about working practices in the mining industry were also factored in alongside environmental concerns, he added.

Forever lab-grown

“We can essentially create the same outcome as nature has created, but at a very, very different price,” he explained, adding that artificial diamonds can be made for as little as “a third of what it is for something that we’ve dug up from the ground.”

“It’s the right thing to do,” he concluded.

Jewelers around the world are looking at artificial diamonds as a way to promote sustainability and cover demand without skyrocketing costs. In 2020, the production of such diamonds reached between 6 to 7 million carats worldwide. Each carat (one carat equals 0.200 grams) produced in a lab means one less carat taken out of the ground, and less environmental impact as a result — so although this shift is based mainly on economic concerns, the environment stands to benefit as well.

This increase in lab-grown stones also echoed in a reduction of the total quantity of mined diamonds. Worldwide, this fell to 111 million carats in 2020, after having peaked at 152 million carats in 2017. Another important driver of this reduction in mined diamonds came down to production-side complications associated with the coronavirus pandemic and a drop in demand.

Pandora will be producing its diamonds in Britain, and that’s also the first country where they will be commercially available.

Customers will undoubtedly enjoy the better designs and lower prices offered by lab-grown diamonds over natural ones, the company feels. Surveys carried out for Pandora also suggest that younger generations are also keen on the environmental aspect of these diamonds, while it doesn’t even make it in the top five concerns for older generations.

That being said, lab-grown jewelry alternatives, such as moissanite rings, have become much more popular in recent times. Technology has improved, researchers have become better at creating more realistic replacements, but there’s a catch: artificial diamonds require a lot of energy to produce. This is needed to generate and sustain the extreme pressures and temperatures needed for synthetic diamonds or diamond alternatives.

A switch to lab-grown gems definitely helps protect natural landscapes and ecosystems. But we don’t yet have a clear-cut road towards diamonds that are truly environmentally friendly due to this energy requirement — energy that is, in large part, still being produced by the burning of fossil fuels. Around 50% to 60% of the world’s synthetic diamonds come from China; coal-fired powerplants still supply the lion’s share of energy here.

Other synthetic diamond-producing countries such as the US have a greater focus on using clean energy (such as hydro) for the process, but overall, the net effect is still quite damaging to the environment.

Still, on the customer’s side, these diamonds are identical to the natural ones. Although there still is a stigma associated with synthetic diamonds, Lacik hopes his company can spearhead the change in perception around these precious, if man-made, stones. It is, after all, a switch made for a very good cause.

“Whether consumers are buying more or less [diamonds], right now is actually not the key driver,” he says. “We want to become a low-carbon business. I have four children, I’m leaving this earth one day, I hope I can leave it in a better shape than maybe what we’ve kind of created in the last 50 years or so.”

Scientists make artificial diamonds at room temperature

Xingshuo Huang is a Ph.D. candidate at the Research School of Physics at the Australian National University. In this image, she is holding the anvil used to create synthetic diamonds at room temperature. (Image: Jamie Kidston/ANU).

In nature, diamonds were formed billions of years ago deep within Earth’s crust under conditions of intense heat and pressure. Typically, diamonds form at depths of around 150-200 kilometers (93-124 miles) below the surface of Earth, where temperatures average 900 to 1,300 degrees Celsius (1650 to 2370 degrees Fahrenheit) and the pressure is around 50,000 times greater on the surface. This is also why diamonds are so coveted — it took millions of years to make them under special conditions.

But now, scientists in Australia are claiming that they can make diamonds in just a couple of minutes — and at room temperature to boot.

Diamonds are forever… but it shouldn’t take that long to make them

Since diamonds are so rare, geologists sought to develop methods to create artificial diamonds. It was only in the 1950s that Swedish and American scientists finally discovered how to convert graphite and molten iron into a synthetic diamond, fulfilling the literary prediction of Jules Verne.

The most common method for creating synthetic diamonds used in the industry is called high pressure, high temperature (HPHT). During HPHT, carbon is subjected to similarly high temperatures and pressures as the carbon that turned into diamonds billions of years ago. 

In their new study, physicists at the Australian National University (ANU) and RMIT University in Melbourne described how they created two types of diamonds. One involves diamonds similar to the kind used in jewelry, the other is a harder-than-usual type called Lonsdaleite created by meteorite impacts.

The amazing thing is that both types of diamonds were generated at room temperature, which is a huge achievement, especially for the rare Lonsdaleite variety that is 58% harder than regular diamonds. However, scientists still had to apply immense pressure onto carbon atoms —  the equivalent to 640 African elephants balancing on the tip of a ballet shoe.

“The twist in the story is how we apply the pressure,” says ANU Professor Jodie Bradby. “As well as very high pressures, we allow the carbon to also experience something called ‘shear’ – which is like a twisting or sliding force. We think this allows the carbon atoms to move into place and form Lonsdaleite and regular diamond.”

River of diamond. Credit: RMIT.

Small slices from the diamonds were cut and then put under the electron microscope so that the researchers could better understand their structure and how they formed. This way, they noticed the materials were formed within bands, which they call “rivers”.

“Our pictures showed that the regular diamonds only form in the middle of these Lonsdaleite veins under this new method developed by our cross-institutional team,” says RMIT’s Professor Dougal McCulloch. “Seeing these little ‘rivers’ of Lonsdaleite and regular diamond for the first time was just amazing and really helps us understand how they might form.”

These artificial diamonds are not meant as jewelry, although there wouldn’t be something wrong to use them in an engagement wrong. Instead, they’re meant for industrial applications where slicing through tough material is required or as protective shielding.

“Lonsdaleite has the potential to be used for cutting through ultra-solid materials on mining sites,” Bradby said in a statement.

The findings appeared in the journal Small.

Ashes to diamonds: how cremated ashes are turned into jewelry

In the U.S. and Canada, more than half of the deceased are cremated. The ashes of a loved one are typically placed inside an urn and displayed at the home of the family or scattered in a particular place that held a special meaning to the deceased person, such as a lake or mountain. Most recently, there’s a third option available to family members for the ashes of their dearly departed: turn carbon-rich ash into diamonds to be worn as jewelry.

If you’re intrigued about how all of this works, read on.

How natural and synthetic diamonds are made

You might be surprised to learn that the seemingly indestructible diamonds and the fragile graphite from which pencil leads are both made of the same stuff: pure carbon. Essentially, diamond and graphite, as well as buckminsterfullerene (the soccer-ball-shaped molecule containing carbon 60 atoms) are all allotropes of carbon — different forms of the same chemical element.

Their incredibly distinct properties are due to the way each material is arranged in different crystal structures. Diamonds are so hard because their carbon atoms are arranged tetrahedrally, resulting in a rigid three-dimensional structure that is phenomenally resistant to compression.

Despite what you might have heard in your high school science classroom, diamonds have nothing to do with coal. Coal is the product of ancient trees and vegetation that got buried deep underground, where it was subjected to high temperature and pressure. The vast majority of diamonds, however, predate the first plants by billions of years and are formed through completely different geological processes.

In nature, diamonds were formed billions of years ago deep within Earth’s crust under conditions of intense heat and pressure. Typically, diamonds form at depths of around 150-200 kilometers below the surface of Earth, where temperatures average 900 to 1,300 degrees Celsius and the pressure is around 50,000 times greater on the surface. Due to occasional magma eruptions, diamonds are forced away from Earth’s belly to the surface in diamond-bearing rock.

Since diamonds are so rare, geologists sought to develop methods to create artificial diamonds. It was only in the 1950s that Swedish and American scientists finally discovered how to convert graphite and molten iron into a synthetic diamond, fulfilling the literary prediction of Jules Verne.

To produce synthetic diamonds, manufacturers employ two main methods:

  • high pressure, high temperature (HPHT) or
  • chemical vapor deposition (CVD)

During HPHT, carbon is subjected to similarly high temperatures and pressures as the carbon that turned into diamonds billions of years ago. The second method, CVD, adds another step to HPHT. Manufacturers will cut a small slice of a diamond seed previously created through HPHT and place it into a high-temperature chamber filled with gas rich in carbon.

Ashes to diamonds

Since the human body is mostly made of water, most of the tissue will vaporize during cremation, forming gases that are released through an exhaust system.

What remains in the cremation chamber is mostly charred bone fragments, which are passed through a magnetic field in order to extract any metal particles. The bone fragments are then crushed into about five pounds of grayish powder — the deceased person’s ashes.

However, turning these ashes into diamond cremation jewelry is not straightforward. The ash isn’t made of pure carbon but rather carbonates and calcium phosphate, with trace amounts of other elements and molecules.

The carbonate is isolated and then decomposed into elemental carbon through a high-heat reduction process in the absence of oxygen. The process produces graphite, which represents around 1% to 4% of the total mass of a person’s ashes.

This graphite is then superheated again to get rid of any impurities, such as salts and boron, leaving graphite that is 99.995% pure carbon. Then from this graphite, high-pressure high-temperature technology, or HPHT, is used to simulate the crushing conditions of natural diamond growth deep within the earth’s crust, in order to convert this carbon from graphite into the diamond allotrope.

The pressure employed to turn the graphite into synthetic diamonds is equivalent to 450 tons sitting on a surface that’s as large as the bottom of a glass.

We’re nearing the final stages of the product — but first, the rough diamond has to be polished. Since these diamonds are typically incorporated into various jewelry — necklaces, rings, etc. — the polishing doesn’t usually take place in a lab.

The end result is a diamond containing a significant proportion of carbon atoms that were present in the body of the deceased person at the time of death, making this a unique way to preserve the memory of a loved one.

Cremation & the Science of Memorial Diamonds

Recently, Professor Dave explained on his YouTube channel exactly how cremation and memorial diamond science works. It’s a fascinating topic, worth examining as cremation rates in the U.S. skyrocket and the memorial diamond industry becomes more well-known.

To begin, when someone passes away, they have the right to specify what happens to their remains.

One obvious choice is to be buried in a cemetery, something that humans have been doing for thousands of years. More recently, people have had the option of donating their body to science, helping to train doctors and surgeons, or potentially aiding in the discovery of a cure to some disease.

In the United States, popular donated body programs are the UCLA Donated Body Program and the Mayo Clinic’s donated body program.

But a third option that is rather popular involves flame cremation. This is where the deceased is placed in a large heating chamber, and reduced to pulverized bone fragments, which we call ashes. According to the Cremation Association of North American, more than half of the deceased in the U.S. are cremated.

How exactly does cremation work?

With so many people choosing cremation in North America, there are a lot of questions that need to be answered. For instance:

  • What exactly are ashes comprised of?
  • What can one do with the ashes once they are formed?

Let’s get to the bottom of these.

Cremation involves placing the deceased body in fire. This is not a new practice. Humans have burned the dead on wooden funeral pyres for ages. But this process has become much more sophisticated in modern times.

Now, we use specialized furnaces called cremators, which are fueled by natural gas or propane. The resulting fire reaches temperatures of about 1,500 degrees Fahrenheit. These high temperatures are possible due to the insulation offered by the cremator, often made of a heat-resistant bricklike material. The whole process can be operated digitally, so as to have total control over all aspects.

The body enters the cremator in something called an alternative container, which will quickly cremate and leave a little ash behind.

But the body will be a different story.

The human body is made of lots of water, many different carbon-based compounds, known as organic compounds, and lots of bone, which is a connective tissue that contains inorganic material, mainly calcium salts, in addition to organic material.

When exposed to the fire, most of the tissues and organs making up the body will vaporize, forming gases that are released through an exhaust system. The same can be said for all the water in the body.

But fragments of bone will remain after the cremation is complete, generally taking about two hours, after which the bone fragments are allowed to cool. They are then swept out and passed through a magnetic field to extract any metal particles that may remain. And then the bone fragments are crushed into a powder to produce the final product, which we call a person’s ashes, about five pounds of grayish powder on average.

So what exactly is in these ashes?

Given that the majority of the components of the body have been vaporized, most of what remains used to be components of the skeleton, which means a lot of carbonates and calcium phosphate, along with trace amounts of other elements.

There will be slight variance from person to person, but the ashes will inevitably reflect the composition of the human skeleton to a large degree.

Now what can be done with the ashes of a loved one?

Some people choose to place them in an urn and display them in the home somewhere. Many request that their ashes be scattered in a particular place that held special meaning to them, like a lake or a mountain. But an additional option has been developed by companies such as Eterneva, and that is to form a diamond using the remains.

Diamonds are made of carbon, as diamond is an allotrope of carbon. Allotropes are different forms that an element can take, which means that carbon atoms can come together to form a network solid in different ways.

Allotropes of carbon include coal, graphite, and even exotic materials like buckyballs and carbon nanontubes. But carbon atoms can also form diamond under the right conditions.

Now we did mention that the majority of the organic matter in the body is vaporized during cremation, but nevertheless some carbon does remain, largely from the carbonates we previously mentioned that are present in bone, and this carbon comprises between 1 and 4% of the total mass of the ashes.

However, we can’t make diamonds out of carbonates, we need elemental carbon, or carbon all by itself, so the carbonates have to be decomposed using a high-heat reduction process in absence of oxygen, in order to get carbon in the form of graphite, without losing any carbon through the production of carbon dioxide in the process.

This graphite is then superheated again to get rid of any impurities, leaving graphite that is 99.995% pure carbon. Then from this graphite, high pressure high temperature technology, or HPHT, is used to simulate the crushing conditions of natural diamond growth deep within earth’s crust, in order to convert this carbon from graphite into the diamond allotrope.

Huge pressures of around 870,000 psi and temperatures above 2,500 degrees Fahrenheit are applied to mimic this astounding natural process, which forces flat sheets of graphite to adopt the three-dimensional tetrahedral lattice of a diamond, thereby attaining the strength and rigidity characteristic of this allotrope.

Apart from a small seed diamond the size of a grain of sand, which functions as the starting point for diamond formation, a metal alloy that acts as a solvent, and the addition of generic carbon to help grow larger diamonds, the end result is a diamond containing a significant proportion of carbon atoms that were present in the body of the deceased person at the time of death, making this a unique way to preserve the memory of a loved one.

It Is Possible Jupiter Could Support Life, Scientists Say

Jupiter and its shrunken Great Red Spot. Credit: Wikimedia Commons.

Jupiter and its shrunken Great Red Spot. Credit: Wikimedia Commons.

A new factor has been added to the debate on whether or not living organisms could exist on Jupiter. You probably know Jupiter is a Jovian planet, a giant formed primarily out of gases. So how could alien life be able to exist in an environment where most of the phases of matter are absent? The answer is simply found in the element of water.

Within the rotating, turbulent Great Red Spot, perhaps Jupiter’s most distinguishable characteristic, are water clouds. Many of the other clouds in this enormous perpetual storm are comprised of ammonia and/or sulfur. Life theoretically cannot be sustained in water vapor alone; it thrives in liquid water. But according to some researchers, the fact alone that water exists in any form on the planet is a good first step.

The Great Red Spot is still a planetary feature which stumps much of the scientific community today. As it has been observed for the past century and a half, the Great Red Spot has been noticeably shrinking. The discovery of water clouds may lead to a deeper understanding of the planet’s past, including whether or not it might have sustained life, as well as weather-related information.

Some scientists have pondered the possibility that, due to the hydrogen and helium content in its atmosphere, Jupiter could be a diamond-producing “factory.” They have further speculated that these diamonds could enter into a liquid state and a rainfall of liquid diamonds would be in the Jovian’s weather forecast.

Likewise, the presence of water clouds means that water rain (a liquid) is not entirely impossible. Máté Ádámkovics, an astrophysicist at Clemson University in South Carolina, had this to say on the matter:

“…where there’s the potential for liquid water, the possibility of life cannot be completely ruled out. So, though it appears very unlikely, life on Jupiter is not beyond the range of our imaginations.”

Scientists are acting accordingly, researching the part which water plays in the atmosphere and other natural systems on Jupiter. They remain skeptical but eager to follow up on the new discovery. They shall also strive to find out just how much water the planet really holds.

diamond

Gem diamonds and ‘worthless’ ones likely have the same origin

The prettiest carbon allotropes of them all, diamonds have fascinated royalty, collectors and window shoppers since ancient times. Some gem-grade diamonds, no bigger than a thumb, sell for tens of million. Most, however, aren’t worth much. But even the most prized diamonds aren’t perfect, and it is these imperfections that might settle and age long debate among chemists and geologists: what’s the source of gem-grade diamonds? A recent analysis suggests both gem diamonds and the largely impure fibrous diamonds stem from the same source.

diamond

Image: Pixabay

Diamonds form at high pressures and temperatures deep at depths of 140 to 190 kilometers (87 to 118 mi) in the Earth’s mantle from carbon-containing minerals. Rising magma then transports the diamonds closer to the surface where they’re mined. Most mines are in African states and Russia.

It takes one to 3.5 billion years for diamonds to form, but fibrous diamonds form more quickly taking only a couple million years. Since they form so fast, fibrous diamonds trap bits of surrounding matter inside the crystal structure which makes them look cloudy.

Geologists know for years that these sort of diamonds contain compounds called carbonates (the stuff shells are made of) and depending on the content you can infer how and where these formed. Gem-grade diamonds typically don’t contain carbonate impurities, so scientists have assumed that these form under different conditions than the fibrous variety.

Geochemists at Hebrew University of Jerusalem carefully looked for inclusions in diamond gemstones. In a couple distinguished for being symmetrical across a central boundary, they found a microscopic inclusion that became trapped along this boundary. When a beam of electrons was fired onto the diamonds, the researchers found 32 inclusions in eight of the thirty samples. Twenty such inclusions were the same carbonate-bearing fluids found in fibrous diamonds. “Visible mineral inclusions (>10 μm) and nitrogen aggregation levels in these clear macles are similar to other MC (monocrystalline) diamonds,” the researchers write.

It's tiny, but geochemists found imperfections akin to fibrous diamonds in gem-grade ones. Credit: Hebrew University.

It’s tiny, but geochemists found imperfections akin to fibrous diamonds in gem-grade ones. Credit: Hebrew University.

This suggests that both older, gem-grade diamonds and the younger variety form by a similar mechanism, the team reports in Earth and Planetary Science Letters

The work “gives us the first strong constraint on how gem diamonds grow,” says Thomas Stachel, a petrologist at the University of Alberta in Canada who was not involved in the research. “People had proposed various explanations for how these diamonds form, but it seems diamond formation is less diverse than we thought.”

It gets very interesting at this point because this means plate tectonics could have already been active 3.5 billion years ago. The most recent research on the matter found modern plate tectonics — complete with its subduction zones, spreading centers, earthquakes and all — probably started about 3.2 billion years ago.

 

 

Oceans of diamonds on Uranus

A new research published in Nature Physics showed that there may be oceans of diamonds (literally) on both Uranus and Neptune. The first ever study conducted on the melting point of diamond concluded that at that certain point, it behaves just like water, with the solid form floating in the liquid form (just imagine icebergs, or small chunks of ice floating in a puddle).

uranus

“Diamond is a relatively common material on Earth, but its melting point has never been measured,” said Jon Eggert (Lawrence Livermore National Laboratory). “You can’t just raise the temperature and have it melt, you have to also go to high pressures, which makes it very difficult to measure the temperature.”

This in itself made the measuring point difficult to find out; diamond doesn’t like to stay diamond when it’s really hot – it tends to turn to graphite (still Carbon, but different crystal properties), which then melts, so the challenge was to find out diamond’s melting point without turning into graphite, which is why they also had to apply pressure.

Now, about Uranus and Neptune. The thing with the two planets is they both have an anomaly; their geographical and magnetic poles have nothing to do with one another, so researchers concluded there has to be an anomaly responsible for the 60 degree deviation of the poles of the North-South axis; on a sidenote: Earth’s poles oscilate too. They even switch polarities, in a very slow and gradual process. They don’t follow the N-S axis, but rather a complicated curve, however, without deviating too much from it (just how much is still debatable).

So what could cause this huge deviation? According to researchers performing the study, it’s extremely likely an… ocean of diamonds. They constructed models which showed the same results and this would also fit with the planet’s chemical composition (over 10% carbon), so this seems more and more plausible. If this is indeed the case, Uranus is definitely Marilyn Monroe’s heaven.

EDIT: before any of you start with the boyish jokes… just don’t do it :)

Diamonds hold the key to primordial life

diamonds

Diamonds are a girl’s best friend, but according to a study led by Andrei Sommer, Dan Zhu, and Hans-Joerg Fecht, diamonds are life’s best friend too. According to them, billions of years ago the surface of these precious gems made it possible for life to rise, by providing just the right chemical conditions.

It is currently believed that life’s earliest forms evolved from something called “primordial soup” of simpler molecules. These authentic building blocks of life however still hold numerous secrets for scientists; the details of how these simpler amino acids molecules were transformed into complex polymers is something nobody has been able to answer yet.

A diamond is basically a cristalized form of carbon, older than the earliest form of life on Earth. By studying them, scientists were able to report that diamonds could have created chemical reactions billions of years ago that created the necessary conditions for life to evolve. They used a lab procedure that included treatment with hydrogen and found out that the diamonds produced a crystalline layers of water on its surface which conduct electricity and are essential for life.

What probably did happen is that when primitive molecules landed on these surfaces in the early atmosphere of our planet, the resulting reaction was probably strong enough to generate more complex organic molecules. As a result, these organic molecules led to the slow but instopable development of life, as we know it today.