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just how eco-friendly are lab-created diamonds? jck

just how eco-friendly are lab-created diamonds? jck

Man-made diamond companies regularly call their product eco-friendly and sustainable. Its now become a basic part of the lab-grown pitch, a way of letting consumers know they are not just getting acheaper product but a meaningful one (though price remainsthe driver, most say). Reporters often print these claims, uncritically.And with concern about climate change clearly on the rise, that could prove a potent positioning.

Yet, these claims are rarely examinedand terminology is often extremely fuzzy. Charlotte Vallaeys of Consumer Reports notes that a term like environmentally friendly has no real definition and could mean whatever the company wants it to mean.

The Federal Trade Commissions (FTC)Green Guides explicitly discouragesbroad, unqualified general environmental benefit claims like green or eco-friendly, as they are difficult to substantiate, if not impossible. Perhaps for this reason, the more circumspect lab-grown companies tend to use word sustainable.

Yet, man-made diamonds are unusual for a sustainable product. They are produced in factories. Granted, theyre mostly clean, modern, nonassembly line factories. But theyre not greenhouses, though some use that term. The machines that produce diamonds require constant energy, 24/7, running huge microwave-heat generators, says one ex-employee.

A single-stone HPHT press will use 175225 kilowatt hours (kWh) per rough ct., which would end up around 6501100 kWh per successful polished ct. A modern larger multistone cubic HPHT press will use 75150 kWh per rough ct., which would end up around 350700 kWh per successful polished ct. Cubic presses come in many sizes, and I would not be surprised if a converted industrial press uses twice that power with a lower success rate and polishing yield.

[A CVD producer] told me [it used] around 60120 kWh per rough ct. and 1,0001,700 kWh per polished ct. There is more unused rough from CVD since they are cube shape, which is why those ratios are higher.

Jason Payne, founder of ADA Diamonds, has said the most efficient growers use 250 kWh per ct., which is the same amount of electricity the average U.S. household uses in 8.7 days or the electricity to fully charge a Teslatwo-and-one-half times. But most use about 750 kWh to grow a diamond, he says.

Singapore-based IIa Technologiesclaimsit uses 77 kWh per ct. to grow diamonds, more than three times its predecessor, Gemesis, which oncesaid it usedonly 20 kWh. But its unclear if these numbers account for mistakes or the post-growth treatment typically done to CVD diamonds.

Diamond mining operations show a similar range of data, which isnt surprising since there are many kinds of mining. Gem excavation in its simplest form means grabbing a shovel and digging, as Diamond Foundry puts it. That requires little energy. The artisanal sector sometimes harms the environment in other ways,which shows why these numbers shouldnt be looked at in isolation.

In a 2013 working paper, Saleem Ali, an environment professor at the University of Delaware, found that Australias Argyle mine uses 7 kWh to produce 1 ct., De Beers operations use 80.3 kWh per ct., and Diavik uses 66 kWh per ct. Alrosa didnt specify its energy use but tells JCK its been significantly decreased.

In an interview with JCK, Ali warned that mining company numbers sometimes dont give the full picture, as they may not account for the costs of exploration and transportation to the sometimes-isolated mine sites. But he says that lab-grown companies also need to provide more info, as some use mined metals in their process.

Industry analyst Paul Zimnisky says that most HPHT diamonds are produced in China, which sources 55 percent of its power from coal and 20 percent from hydro. In India, another major producer, 75 percent of grid power comes from coal and 10 percent from hydro. Singapore, home of IIA, uses little renewable energy.

Diamond Foundry says its been certified carbon-neutral, though it purchases solar credits to get there. Certifier Natural Capital Partners declined to talk to JCK about its methodology but pointed us here. The steps required for certifying carbon footprint are a full third-party audit, says Diamond Foundry CEO Martin Roscheisen via email. It is comprehensiveit includes employees driving to work, all of our operations worldwide including polishing, etc.

On the mined side, Diamond Producers Association (DPA) CEO Jean-Marc Lieberherr says that mining companies are looking at reducing their carbon footprint, and De Beers hopes to soon make some mines truly carbon neutral, using carbon from the diamonds. TheDPA recently hired Trucost, a division of S&P Global, to assess its members, which comprise 75 percent of world production.

Trucost found that the carbon footprint is the biggest environmental issue in diamond miningand like Payne, its come up with a consumer-friendly analogy: Carbon emissions associated with one polished carat are six times less than those of one passenger on a one-wayflight from Los Angeles to New York.

Which sidewins the energy wars? Its not cut and dried, says Ali. Depending on the process and the location of the mine, the data can be highly divergent and cannot be used as a singular measure of environmental impact, he wrote. [T]he energy usage for synthetic diamonds on a per-carat basis may still be considerably greater than for mined diamonds because of issues of scale.

So, in some cases the lab-grown companies compare favorably; in others, they dont. We need more info, and more transparencyaround these numbers and claims, to get the full picture. These are both energy-intensive processes. For now, theeco-energy claims are, as the FTC puts it, difficult to substantiate.

The second eco-argument says that diamond mining rips up the land and damages fragile ecosystems, including wildlife and lakes. One frequently quoted statisticis it takes 250 tons of earth to find1 ct. of polished diamond.

The footprint of a diamond is narrow, says Lieberherr. There is no chemical used in extracting diamonds from the ore, and water gets largely treated and recycled. Modern mining is done under very stringent environmental controls from local governments and communities. Canada, for example, has some of the most stringent environmental norms in the world.

Trucost calculated that DPA members collective negative impact on land usage, water depletion, pollution, and waste is compensated by the positive benefits associated with their biodiversity programs. All told, theyve conserved 260,000 hectares of land, Lieberherr says.

Still, issues do pop up, particularly in poorly managed areas. Perhaps the worst recent issue came from the Marange diamond fields in Zimbabwe, where miners were accused of dumping chemicals in the water. Incidents like these are relatively rare, thoughhardly nonexistent, and the (non-DPA) companiesthat allegedly did these things bear responsibility for them. But it shows that mining can have a wide range of effects and why its better to know what youre getting.

Yet, hes reluctant to endorse lab-created diamonds because, again, theres a bigger picture. Some 10 million people work in the diamond industry, in some of the poorest areas of the world. The diamond industry contributes $8 billion a year to Africa.

That was echoed by just about every nongovernmental organization (NGO) that JCK talked to. Its striking that no conservation group has endorsed lab-grown diamondsthough plenty have endorsed electric cars. We reached out to environmental organizations on this issue. None responded.

Joanne Lepert, executive director of Impact, a Canadian NGO active in African development thats often critical of the diamond business, says that for us, sustainability is linked to economic development, its about structural change, its about womens rights, and its about inclusive participation. Synthetic diamonds dont do any of that. They will take that away. Its closing the door on the micro-producers to enter the international market.

Brad Brooks-Rubin, policy director of the Enough Project, another sometimes-critical NGO, has said, [Lab-diamonds] focus on the environment, but a bigger question is, is it ethical to guide people away from buying diamonds in developing countries, where a million people or more rely on the work?

Estelle Levin-Nally, founder of Levin Sources, which works on better governance in the natural-resource sector, says, It depends on what your consumers care about: Do they care about the environment or poverty and people who want to eat and feed their family?

If you believe in technology and getting rich, then go with lab-grown diamonds, she says. If you believe in the fair distribution in income across the whole community, you might want to rethink that.

This isnt about the diamond industry being good or badthe business hasplenty of both. Its about an undeniable fact: Millions of people and their families depend on diamond mining, and if you hurt their business you risk hurting them. The economies of poor countries are also fragile ecosystems.

Some argue these millions of workers should transition to more eco-friendly livelihoods. But they do it because theres no other choice. Theres no solar-panel business waiting to be born in Sierra Leone. Ali has pointed out that before Botswana became a major diamond producer, its main business was cattle ranching. That was less lucrative and also bad for the environment.

On the plus side, lab-grown diamonds have probably kept some Indian cutters employed and maybe even some small jewelers in business. Industrial synthetics have shown enormous promise for everything from computers to health care. And mining reserves are dwindling, though it will take decades before they actually run out.

There are no easy answers here. But perhaps were looking at the wrong question. Maybe we shouldnt be looking at the ecological and social impacts of these broad categories, but the impact of each specific stone. People shouldnt buy a sustainableitem without knowing its precise impact.

That would require a more transparent supply chain.For now, both sectors lag on this: Mined diamonds and lab diamonds are usuallyaggregatedandon occasionmixed together. And they both share the same risks: A 2013 report from the Financial Action Task Force warned that created diamonds are just as vulnerable to money laundering as their mined counterparts.

According to Common Objectives, a sustainable fashion initiative, a transparent business maps its supply chains, details the provenance of its supply, and reports its social, environmental, and financial results. This transparency should be standard for any business that boasts that its sustainable or ethical, and, needless to say, transparent.

For now, saying a diamond is lab-grown is like saying it has a Kimberley Process certificate. It tells you some info, but not all. Even if lab-growns are more eco-friendly than mined, thats an arguably inappropriate labelto put on an item produced with large amounts of nonrenewable energy. If a cookie contains 30 percent less sugar, that doesnt make it a health food.

Im not against lab-grown diamonds, she says. She notes there is a growing movement towardclimate-smart mining, including a new initiative by the World Bank. If lab-grown diamonds help with that, bravo.

Ill be covering this subject in a future feature in JCK, so I welcome more info, feedback, and data. We also discussed this issue on the pilot episode of JCKs new podcast, The Jewelry District. Finally, for a further lookat this topic, I recommend this article in Jewellery Business.

mineral stone briquette process in bangladesh

mineral stone briquette process in bangladesh

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machines used in coal mining | career trend

machines used in coal mining | career trend

Coal mining has been performed since the arrival of the Industrial Revolution in the mid-18th century. Coal is used as a fuel primarily for steam-generated electrical power plants, as well as being a component of certain industrial applications, such as steel manufacturing. Coal is widely distributed over the planet, either as underground seams which must be mined, or as deposits located closer to the earth's surface. The latter can be extracted at the surface by removal of the topmost layer of earth and rock covering the coal seam.

More than two-thirds of coal extracted underground is done by a "continuous miner," a tractor with a mounted cylindrical grinder that breaks coal away from the seam. The continuous miner deliberately leaves undisturbed pillars of rock and coal in the mining area to create natural supports for the ceiling. This is known as "room and pillar" mining. When most of the coal seam has been extracted, the pillars then are mined one by one, allowing the roof to naturally cave in.

Twenty percent to 30 percent of mined coal underground is from longwall mining. This is performed by a mechanical cutter that shears coal off from a panel on the seam. The panel being worked on may be up to 800 feet in width and 7,000 feet in length. Mined coal is deposited onto a conveyor that moves the coal to a collection area. Hydraulically powered shields over the machine provide ceiling support. Longwall mining is more efficient than room and pillar mining, but the equipment is more expensive.

For extracting coal which lies close the surface, huge drag-line shovel machines remove the topmost layers of soil and rock, exposing the coal, which is then removed by smaller machines. Surface mining may involve removing sections of hills or top layers of a flat surface area. The layers of rock and dirt covering the coal are reserved for until the coal is removed, at which point the the dirt and rock is replaced, the mine covered over, and the environment restored as much as possible to its original condition.

Conventional mining employs crews of miners who use explosives and drills to extract coal, which is then loaded onto cars for transport to the surface. This method presents higher risks to miners because of the explosives. The coal dust generated by the drilling and explosives is also a health hazard when continuously inhaled. This is the oldest method of coal mining.

Based in Los Angeles, Peter De Conceicao has been a professional researcher and writer since 2000. He has also worked as a writer for nonprofit educational organizations. Most recently, his work has appeared in Examiner.com as a news analyst and social commentator. He holds a degree in communications from Loyola Marymount University.

a hunt for dark matter in a former gold mine - los angeles times

a hunt for dark matter in a former gold mine - los angeles times

he scientists don hard hats, jumpsuits and steel-toed boots to pile into a metal cage for a rumbling 11-minute descent into an abandoned South Dakota gold mine. They step over old mine-cart rails, through rough-walled tunnels and into a bright white room. There, they cast off their dusty garb and enter a lab hidden nearly a mile beneath the Earth.

"Is everyone ready?" the Case Western Reserve graduate student calls out over growling machinery filling the cavernous space. Ice piles on a nearby tank, digital displays glow green, and bundles of wires curl in every direction.

Here, with a two-story state-of-the-art detector sheltered in what was once North America's deepest gold mine, the scientists are panning the cosmos for a flash of something far more elusive than gold: dark matter.

Dark matter outnumbers normal matter in the universe 5 to 1, yet remains one of physics' ultimate mysteries. It can't be seen or felt, and passes through Earth like a phantom. Scientists think it might be made of hypothetical "weakly interacting massive particles" WIMPs though they have yet to find one.

On the rarest of occasions, a dark matter particle might just bump into a normal-matter atom. The trick is to catch that signal amid the hail of cosmic particles bombarding Earth so thickly that hundreds pass through your body each second.

Scientists strain their ears for that dark matter whisper against the background roar. They dig deeper and deeper into the Earth, to mute the cosmic noise. They fill tanks with liquid xenon that's dense as rock, armor it with a 70,000-gallon shield of water and wait for particles to hit it.

Before "turning on" the detector for the first time this day in early February, several researchers spend hours going through their checklist, closing dozens of valves to control the flow of xenon. It's a painstaking process, and they toil in pairs to check each other's work. Phelps calls out the valve numbers: 15, 16, 30, 31.

Xenon is costly, but the scientists say it's worth the roughly $1,000-per-kilogram price tag. Like a field full of brawny defensive linemen standing shoulder to shoulder, the massive atoms in the dense liquid block out unwanted particles and raise the odds of trapping a slippery dark matter particle trying to squeeze by.

These players are also self-disciplined. Xenon is so chemically inert that electron signals from any collisions can pass freely through the liquid. These crucial signals let scientists eliminate phony dark matter candidates.

Once the researchers release the xenon to fill the detector, they'll have to carefully control the flow. If it gets too warm, the pressure will surge as the liquid evaporates. If it gets too cold, ice can form and wreck sensors inside.

If the pressure does spiral out of control, burst discs will explode and allow precious xenon gas to pour into a giant black balloon. The deflated bag stretches across the cavern, a worst-case scenario hanging over their heads.

"I'll feel a lot better once we've actually started. Because until we've started, I'm not 100% sure it's going to work," says Simon Fiorucci, the Brown University physicist who's been wrangling the detector's operations on-site. He's 98% certain, he adds. "But we've been burned by 98 before."

The lead scientists may rule the project, but the grad students own it. They've spent long, intimate stretches with the detector, and it shows. When a device needs ventilation, they drill a lopsided smiley face into it. When they need to cool down some xenon, they pour liquid nitrogen into a blue Igloo picnic cooler.

The Large Underground Xenon (LUX) detector inside a former South Dakota gold mine is designed to pick up traces of dark matter. (Graphic by Lorena Iniguez Elebee; Graphic reporting by Brady MacDonald) Interactive graphic

"It's efficient for holding," Dobi explains. Then he pauses. "If you want to play with liquid nitrogen, we could get some for you. Feel free to freeze your lunch and then shatter it into little pieces."

The resemblance is no accident. Many of LUX's lead scientists have seceded from the European collaboration, whose future experiments would be cramped for space. The physicists faced a choice: help build the next experiment in Italy, or try for a larger detector that would take longer to build but whose greater volume would offer far more sensitive results.

In the 1960s, in the same cavern where LUX now sits, physicist Ray Davis persuaded the mine's operators to let him immerse a tank of dry-cleaning fluid in water to capture neutrinos from the sun. His experiment helped show that neutrinos had mass, contradicting the standard model of particle physics, and earned Davis part of the 2002 Nobel Prize in Physics.

When Homestake officials told physicists in 2000 that they would be shuttering the mine, scientists saw a golden opportunity to turn it into an underground lab. It would make the U.S. a major player in the deep science game.

Scientists will watch for a two-flash combination to occur when a dark matter particle collides with highly purified xenon inside the detector. (Graphic by Lorena Iniguez Elebee; Graphic reporting by Brady MacDonald) Interactive graphic

The National Science Foundation spearheaded the operation. The Department of Energy joined the effort. The state of South Dakota population 833,000 poured more than $40 million into the project. Local businessman and philanthropist T. Denny Sanford tossed $70 million into the pot. His namesake Sanford Lab would inhabit the mine. LUX would be the first major science experiment completed at the facility.

Then in 2010, the National Science Foundation abruptly pulled back, balking at the idea of running such a lab. Caught off-guard, the Department of Energy weighed whether to take over. Even as the lab's fate hung in the balance, the LUX scientists kept working.

Now, ready to finally fill the detector with super-purified xenon and bring the experiment to life, the graduate students are ecstatic. They open the bottles with ceremony, smiling at the valve's first hissing pop of air as if it's from a bottle of champagne.

Fiorucci, sitting cross-legged among the detector's machinery as he diagnoses the problem, isn't too concerned. The detector is working the team just don't know what exactly is happening in it right now. And he can wait. He's not even expecting to find dark matter.

Within three days, the detector will fill up with more than 800 pounds of xenon cooled to minus 148 degrees Fahrenheit. In the weeks ahead, they'll start circulating the xenon and pulling out impurities, preparing LUX to start taking dark matter measurements.

For now, many of the grad students are ready for a well-earned break. Paper unicorns pop up in surprising nooks around the lab, bearing Technicolor testament to the demanding hours the scientists have spent underground.

Careers in the entertainment industry can be mysterious for those just starting out, and even for those working in the business. The Los Angeles Times brings you explainers and advice for starting and building your career in Hollywood.

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From our initial contact and throughout the procurement process the people from Security Detection were extremely helpful and provided expertise in assisting us in making the correct choices for our facility.

Delivery and installation went exactly as prescribed. Training services were also provided by Security Detection personnel for our entire staff. It consisted of both classroom and practical exercises. The training provided was most effective and gave our staff valuable pre event experience in the operation of the equipment provided.

All post installation questions and concerns have been addressed in an efficient and expeditious manner. Our complete satisfaction has always been the goal of Security Detection personnel and they have continuously met that goal.

For the past 2 1/2 years, Warner Bros. Theatrical Distribution Division has been utilizing metal detector services provided by Security Detection Inc., this company was highly reccommended to us by one of our anti-piracy security vendors.

During the past 5 years our company has worked closely with Rob Paradise, Assistant Director of Eastern Region on the purchase of 23 walk-thru metal detectors for our facility. Security Detection offers high quality service and has proven to be a reliable and dependable company.

Rob maintained a consistent and trustworthy demeanor throughout the entire process. His responsiveness to requests and questions were met without any concern. The Security Detection team provided training to our staff and was always there to offer assistance and troubleshooting when needed.

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