2012年10月26日星期五
Classifications of Tungsten Filament
Lots of tungsten filaments are used all around the world. I think the attached two photos are included lots of it.
Contact sales@chinatungsten.com or go to www.tungsten.com.cn for more detail.
2012年10月11日星期四
Novelty Tungsten
In recent weeks tungsten bars encased in gold have surfaced in Manhattan and
elsewhere around the globe. They look and feel like the real McCoy. They are
good enough to pass the casual examination of experts (e.g., Patrick Heller’s
NumisMaster columns June 5 and Sept. 25).
The problem of fake gold bars, or gold coins for that matter, is not new. A quick web search will show numerous reports of bogus bars from the past decade alone. For example, on Nov. 18, 2009, Kitco reported four 400-ounce gold bars shipped from the United States to Hong Kong as proving to be gold-plated tungsten. Then in February 2010, employees at Germany’s W.C. Heraeus, the world’s largest privately owned refinery, came across a 500 gram tungsten-filled gold bar received from an unidentified bank.
However, this time around the story has grown legs. It has taken on a life of its own. Some media reports and particularly a number of web blogs have sensationalized the issue. Several claim that the latest discoveries are the merest tip of an enormous tungsten-filled iceberg that affects the gold holdings in major world stockpiles – including Fort Knox. No doubt an online Sept. 23 report that 60 tons of tungsten-filled gold bars turned-up in an unnamed Asian depository has helped fuel the flames of conspiracy. However, I have been unable to substantiate this story.
But for most of us it is the more mundane matter of ensuring the 500 gram gold bar we brought as security against a rainy day is the genuine article. Folks in this category may be taken aback when they realize the quality of some of the current crop of fake bars and where these are turning up. While both aspects are concerns, high-grade fake bars have been around for decades.
Sadly such bars are quite easy to produce – by anyone. Try Googling, “How to make fake gold bars.” A Popular Science article from 2008 will probably be near the top of your search. It tells anyone with a half-decent machine shop and a supply of gold and tungsten how to go about it.
Tungsten has a density of 19.25 g/cc compared with gold’s 19.30 g/cc, but unlike gold, tungsten is not particularly easy to work. It can’t be readily cast into ingots. However, slugs and machined bars of the metal are readily available. It currently sells for about $35 a kilogram against $57,000 a kilogram for gold.
The classic do-it-yourself fake involves drilling holes in genuine gold bars and filling these with tungsten rods. Repairs to the bars have to be done carefully but a competent metal-worker can make an acceptable product that will pass superficial tests.
This drill-and-fill approach is best-suited for small bars. For larger items such as 10-ounce or standard 400-ounce gold bars the trick is to gold plate or gold dip a tungsten core. The bar is then cleaned up and fake stamps impressed on it.
For better quality fakes no expense is spared to produce a superior product. A gold layer some 5-6 millimeters thick is commonly used. Not only does this foil superficial testing but frustrates non-destructive instrumental analytical procedures such as x-ray fluorescence.
Even if the cost to produce a top-quality fake 400-ounce London Good Delivery Bar is some $50,000, a fraudster can pocket a profit of over quarter of a million dollars per bar per sale, all presumably tax-free.
But if do-it-yourself lacks appeal, China Tungsten, www.chinatungsten.com, will sell you as many tungsten-filled gold bars as you would like. The site is an eye opener. The company is totally up-front about what it is doing. Among other products they are selling expensive novelty items: gold-coated door stops or paperweights that happened to be shaped as for standard ingots. Anyone wanting to dabble in the gold market should visit this site before buying. Click on “Tungsten Gold” in the index and read on.
I also recommend the collection of videos listed on the China Tungsten website. They appear to be sourced from across the world.
Two points must be noted. The production of tungsten-filled gold bars is by no means the sole preserve of China. There is evidence that it has happened in the United States. Secondly, as in all aspects of buying and selling, the responsibility is with the purchaser: Caveat emptor. Buy from a reputable source and go fully armed with knowledge.
Claims are made on the Internet of various ways in which tungsten-filled gold bars – and coins – can be identified. At least one YouTube video claims ultrasound works. This is the way modern medical science can track a woman’s pregnancy. The procedure for gold bar analysis is nearly identical.
I am not in a position to verify the efficacy of this approach. I have no tungsten-filled bars to experiment on. If any reader who has seen this done successfully can inform the editor, we might all sleep a little easier.
The problem of fake gold bars, or gold coins for that matter, is not new. A quick web search will show numerous reports of bogus bars from the past decade alone. For example, on Nov. 18, 2009, Kitco reported four 400-ounce gold bars shipped from the United States to Hong Kong as proving to be gold-plated tungsten. Then in February 2010, employees at Germany’s W.C. Heraeus, the world’s largest privately owned refinery, came across a 500 gram tungsten-filled gold bar received from an unidentified bank.
However, this time around the story has grown legs. It has taken on a life of its own. Some media reports and particularly a number of web blogs have sensationalized the issue. Several claim that the latest discoveries are the merest tip of an enormous tungsten-filled iceberg that affects the gold holdings in major world stockpiles – including Fort Knox. No doubt an online Sept. 23 report that 60 tons of tungsten-filled gold bars turned-up in an unnamed Asian depository has helped fuel the flames of conspiracy. However, I have been unable to substantiate this story.
But for most of us it is the more mundane matter of ensuring the 500 gram gold bar we brought as security against a rainy day is the genuine article. Folks in this category may be taken aback when they realize the quality of some of the current crop of fake bars and where these are turning up. While both aspects are concerns, high-grade fake bars have been around for decades.
Sadly such bars are quite easy to produce – by anyone. Try Googling, “How to make fake gold bars.” A Popular Science article from 2008 will probably be near the top of your search. It tells anyone with a half-decent machine shop and a supply of gold and tungsten how to go about it.
Tungsten has a density of 19.25 g/cc compared with gold’s 19.30 g/cc, but unlike gold, tungsten is not particularly easy to work. It can’t be readily cast into ingots. However, slugs and machined bars of the metal are readily available. It currently sells for about $35 a kilogram against $57,000 a kilogram for gold.
The classic do-it-yourself fake involves drilling holes in genuine gold bars and filling these with tungsten rods. Repairs to the bars have to be done carefully but a competent metal-worker can make an acceptable product that will pass superficial tests.
This drill-and-fill approach is best-suited for small bars. For larger items such as 10-ounce or standard 400-ounce gold bars the trick is to gold plate or gold dip a tungsten core. The bar is then cleaned up and fake stamps impressed on it.
For better quality fakes no expense is spared to produce a superior product. A gold layer some 5-6 millimeters thick is commonly used. Not only does this foil superficial testing but frustrates non-destructive instrumental analytical procedures such as x-ray fluorescence.
Even if the cost to produce a top-quality fake 400-ounce London Good Delivery Bar is some $50,000, a fraudster can pocket a profit of over quarter of a million dollars per bar per sale, all presumably tax-free.
But if do-it-yourself lacks appeal, China Tungsten, www.chinatungsten.com, will sell you as many tungsten-filled gold bars as you would like. The site is an eye opener. The company is totally up-front about what it is doing. Among other products they are selling expensive novelty items: gold-coated door stops or paperweights that happened to be shaped as for standard ingots. Anyone wanting to dabble in the gold market should visit this site before buying. Click on “Tungsten Gold” in the index and read on.
I also recommend the collection of videos listed on the China Tungsten website. They appear to be sourced from across the world.
Two points must be noted. The production of tungsten-filled gold bars is by no means the sole preserve of China. There is evidence that it has happened in the United States. Secondly, as in all aspects of buying and selling, the responsibility is with the purchaser: Caveat emptor. Buy from a reputable source and go fully armed with knowledge.
Claims are made on the Internet of various ways in which tungsten-filled gold bars – and coins – can be identified. At least one YouTube video claims ultrasound works. This is the way modern medical science can track a woman’s pregnancy. The procedure for gold bar analysis is nearly identical.
I am not in a position to verify the efficacy of this approach. I have no tungsten-filled bars to experiment on. If any reader who has seen this done successfully can inform the editor, we might all sleep a little easier.
Tungsten Price in October, 2012
These
days, the direct price of tungsten in October has been open by several
influenced companies, including China Minmetals Corporation. The price in
October of tungsten will be increased a little compared to the last month. The market
of tungsten has been more active. Most suppliers are still offering higher
price than last month. Therefore, the price of tungsten becomes stable and
stable, and will increase in the later time.
Since
the price of tungsten is moving to a stable trend, the price of tungsten scrap
is also becoming steady. The price of tungsten carbide drill scrap is about
186~188 RMB/KG without VAT price. The larger tungsten carbide drill scrap is a
little higher at 190~191 RMB/KG. Tungsten cube scrap is 206-210元/kg.
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