Bitcoin Forum

to all the goldbugs out there, beware!

Tungsten-Filled 10 Oz Gold Bar Found In The Middle Of Manhattan's Jewelry District

http://www.zerohedge.com/news/tungsten-filled-10-oz-gold-bar-found-middle-manhattans-jewelry-district

http://www.zerohedge.com/sites/default/files/images/user5/imageroot/2012/09/fake%20gold%203_0.jpg


 

Bad news: I just checked one of my Bitcoins. I opened it up, and inside I actually found a LiteCoin!!!  This is a serious problem. I'm worried if I check my other Bitcoins the same thing will happen :/  Should I tell Gavin?

Hey, it could be worse. You could have gotten a bunch of Microcash.

FTFY

shit

they must have salted it with some folded proteins to make up the difficulty

This is actually more wide spread than you think, I know lots of Chinese factories are producing
these tungsten filled "gold bars" that is flooding the market. Most of the time even the merchant would not
know, since it's difficult to know unless you destroy the bar and reveal what's inside. I think at least
20% of gold bars on the market right now, are tungsten filled.

Lucky you. I hurried to test my Bitcoins .. opened them .. and found that they are inside made of just some random ASCII letters! Damn!

I found chocolate in mine... at least it wasn't a complete waste.

LOL chocolate would be better than tungsten... that's kinda funny :)

ITT we find out the US seized everyones gold and has now cornered the market on tungsten  ;D

I'm going long on tungsten tomorrow.

I was wondering why Tungsten and not Lead (which has a higher atomic number than Gold):
- http://en.wikipedia.org/wiki/Tungsten (http://en.wikipedia.org/wiki/Tungsten)

specific gravity

The funny part is that these polished, stamped, numbered bars tend to fetch a premium over the spot price.  This makes them easy targets, since the owners would be less likely to perform any type of destructive testing on them.

Can't these bars be tested electrically? Pump enough current through, and the performance characteristics of a solid gold bar should be sufficiently different from a gold-plated tungsten bar... Or would the current have to be high enough that you'd just melt part of the bar, thereby not solving the non-destructive test problem?

Meh. Seems like there's a business selling reliable non-destructive gold-bar test equipment somewhere in here... 

You'd be quite right in suggesting that the conductivity characteristics would change, tungsten has resistivity of 5.60e−8 Ω⋅m (at 20C) where gold has resistivity of 2.44e-8 Ω⋅m. You're also right in suggesting that you'd need quite some amperage to measure anything more than surface conductivity, which would be unchanged since the shell is still gold.

There are other characteristics that would probably be more useful - the speed of sound through tungsten differs from the speed of sound through gold, so an ultrasound could be used. Electrical conductivity could also be used in the form of eddy currents, introduced inductively, since they have more penetrating power than just passing current through the bar.

Ultrasound would probably work. you could see the boundary layer between the gold and tungsten.

Use ultra sound http://www.youtube.com/watch?v=5FvM_4B7Pkc

We have that same risk with physical bitcoins.    I hated to peel a 25 BTC coin I had purchased as it holds a premium over the 25 BTC it protected by the hologram.  But I did eventually for two reasons, one -- I wanted to be able to confirm first-hand that the code underneath was truly valid -- funded and matched the code on the outside of the coin.  The second reason is because I'ld nearly lost it several times showing it around (as a prop whenever I'm describing Bitcoin to someone in-person.)  At least now, fully spent, I'm only losing a few dollars worth of value if it gets lost.


Here's the tungsten incident from earlier this year:

https://i.imgur.com/VgFB9.png

Bitcoin, 100% Pure w/No Tungsten - Miners Make Sure Of It

  - http://www.bitcoinminer.com/post/19914661084

there are no physical bitcoins.

The term physical bitcoins refers to a method of using an offline storage medium for temporarily containing and masking the private key to a bitcoin address. Some devices are trustworthy enough for small amounts for them to be traded without online verification.

Use gold coins, preferably those under an ounce. Harder to drill, more work, less benefit, greater likelihood of getting caught than using 10 oz bars.

I am not 100% certain, but I would imagine that tungsten-filled coins would sound differently when dropped on a glass table than real gold coins.

I think up to 100gr goldbars are safe for the moment. All the filled bars in the pics so far have ben 500gr and up.

If Tungsten ha higher specific gravity than Gold, they will have to mix The tungsten with something or the gold bar will be to dense!

the difference is extremely small: http://www.wolframalpha.com/input/?i=%28density+tungsten%29+%2F+%28density+gold%29

Right.

Gold is 19.30 g/cc
Tungsten is 19.25 g/cc

So we're looking at a difference of 0.26%. On a ten troy ounce gold bar that's 311.25*.0026 = 0.81 grams if the whole thing is tungsten. Since some of it is real gold, the bar will weigh roughly a half gram more than it is supposed to, on a 311 gram bar.

What is the normal mass tolerance on a pamp suisse gold bar?

well, if it says 311 gramm, it will weight 311 gramm. what they change is most likely the size! i.e. a fraction of a mm on a non-even surface (where the embossed numbers and letters are) is impossible to notice.
therefore, one has to measure the actual volume, which is pretty hard.

I'm somewhat certain that when gold buyers buy gold, they actually use two electrical probes that measure the resistance and if it's too high, it's not pure gold or it's plated whatever.  I suppose with that much thick surface gold or in the 2nd pic there, the electricity would simply travel around it in a significant enough level to not detect the tungsten.  Anyone know?

Btw I opened up my BTC wallet and found just a note that said my bitcoins' kidneys were missing and they needed to go to the hospital ASAP!

This is actually possible on a Casascius Coin, where someone can add Litecoins to it, and has been done before.

It is possible to compute the equivalent Litecoin address from the Bitcoin address with my Bitcoin Address Utility, and then it just uses the same private key.

But does Pamp Suisse guarantee that their bars are 10.00000000000000000000 troy ounces exactly? Surely there is a tolerance, such as + or - .001 troy ounces Or .01 troy ounces.

No, they are cast into a form with a nominal weight, then measured very accurately.  They are then sold at their actual weight, not the nominal weight.

Ultrasound might work as long the tungsten is a bar or rods. What if the tungsten is a powder mixed in the inner portion of the gold bar?

maybe "Neutron Activation Analysis" would work: You shoot neutrons into the sample and Gamma ray energy, distribution and decay says something about the elements in the sample. It can detect even faint traces of other elements. Not for home testing, but quicker and less wasteful than recasting.

inb4 archimedes #eureka

My Bitcoins are filled with doubt

his method is so inexact, it wouldn't work at all. you know, water has this nasty thing of "surface tension"

I just wrote my private key onto a light bulb to test this - the private key was then projected onto my curtains when I turned the light on.
Tungsten and bitcoins are a dangerous combination.

use oil then. this method should be pretty exact. Worst case you'd have to get some lab glassware to have precise volumetric measurements.

Getting accuracy of better than 0.1% might be pretty tough even with lab equipment, especially when one of the surfaces is embossed.

Don't see any problem if these bars r used as legal tender. Noone should care what is inside. Tungsten is even more valuable than paper inside dollar banknotes.

It would be pretty tough, you are right, and would require some laboratory skill. 19.25/19.30 is a thin margin.

The conductivity test or ultrasound would probably be the easiest.

Here is a way to test without ultrasound equipment.

First dip gold in water to find the amount of displacement.  The displacement will give you a very accurate volume of the bar.  Now using a scale measure the weight of the bar.  Using the volume and the atomic weight of gold you can also calculate weight.  If the calculated weight and measured weight are the same it's a real bar.  If it is lighter then it might have tungsten in it.  Something like that.

Tungsten is a common element with little inherent value. If people buy gold bars, they expect to be buying a certain quantity of rare, expensive, precious gold, not common tungsten you can find in every lightbulb.

As others have said, it is difficult to calculate a small volume such as a 10 oz gold bar to an accuracy of 0.25% using the "dip in water" method. You would need to be more accurate than 0.25% to detect tungsten in the bar.

devious.  sure sign of a top.

I often buy bullion but I shy away from really large bars as there is too much opportunity for fraud. (too much temptation with current prices) I feel safer with bullion coins (American eagles, Canadian Maple Leafs Austrian Philharmonics) from a reputable dealer. I evaluate each coins markings and measure each coins weight and size carefully before It goes in my vault

as written above, this is pretty hard.

second, and as an additional point why this doesn't work: you can mix the tungsten with small amounts of some other very cheap element to get the exact density of gold. then, both parts (pure gold, and the tungsten+something mix) have exactly the same density.

Heh.  No. (http://chemistry.about.com/od/elementfacts/a/elementdensity.htm)

no he's right. you could toss a little platinum in there to offset the weight to have a net equivalent density of gold in the same volume.

in the end you'd really have to go to more complex testing eg ultrasound or conductivity

Don't worry about gold bars. We have bitcoins.

Platinum? Let's keep things cheap while we're ripping people off. A proper ratio mixture of lead and tungsten could have the exact density of gold.

Show work please, then apologize.

According to my back of the napkin calculation, you'd only need to add 1.5% platinum to tungsten by volume to get the same density as gold. That would be a pretty minimal expense.

It's worse: http://www.exohuman.com/wordpress/2011/02/fake-gold-bars-sold-to-china/

possible 1.3 million Tungsten bars (for 400 ounce gold bars) ordered to fake Fort Knox bars and later sold of to China. The FED apparently knowing about this!

Is this really true? Are such stories spread for gold market manipulation?

Platinum is cheaper than gold (Crazy, right?) and lead is 1/2 the density. Pt is the cheapest element that has a higher density than gold.

The equation that would need to be fulfilled is:

p_Au*f_Au + p_Pt*f_Pt + p_W*f_W = p_Au, for the bar to pass the archimedes (effective density) test.

where p_x is the density of element x and f_x is the volume fraction of element x.

p_Au = 19.282, p_Pt = 21.46 and p_W = 19.25. This equation is subject to the constraint f_Au+f_Pt+f_W = 1.

The price of W is $45/kg, which is $1.28/oz. Gold price = $1771/oz., Platinum price = $1638/oz.

Now we can establish the price of the bar as a function of the volume fractions.

The price per oz. of the forged bars is given by P_bar(f_Au, f_W, f_Pt) = P_Au*f_Au+P_Pt*f_Pt+P_W*f_W, which we would like to minimize given the above density and volume constraints. This arrives at an edge solution (max. amount of W, no Au in bar), at f_W = (p_Au-p_Pt)/(p_W - p_Pt) = 98.4vol.% W, 1.6vol% Pt.

This bar would cost $27.40/oz. and have exactly the same apparent density as a gold bar.

Of course, it would not look like gold, but basically you could add any amount of Pt/W in this proportion (98.4% W, 1.6% Pt) to the gold bar, and you would not change the effective density.

loool! That was a good one :)

Jim Sinclair’s Commentary

My opinion is this is disinformation. The diamond district in NYC is Hassidic Jewish.

Nobody cons those guys.

http://www.jsmineset.com/2012/09/19/in-the-news-today-1314/ (http://www.jsmineset.com/2012/09/19/in-the-news-today-1314/)

ah, well, in my head, i mixed their order, ... but basically i'm still right.
also, instead of platinum, you can use http://en.wikipedia.org/wiki/Osmium#Price (or iridium, maybe)

there are https://www.casascius.com these coins :P

measuring the volume is trivial with something as small as a 1 oz bar. Just drop  it into a graduated cylinder of water and note how much the level changes.

It's theoritically trivial but in practice finding a graduated cylinder of sufficient accuracy is not.

Incorrect, the specific gravity test used to be very safe, modern fakes using a mixture of tungsten and osmium precisely match gold's specific gravity.  Sad but true

hmm, I would hope the much cheaper price of silver vs gold would keep people from trying to scam silver like this.

Then again with the less valuable nature perhaps testing is even less common practice.

Makes you wonder how much paper certificates for gold or gold in vaults (eg. goldmoney) is actually fake. No one would ever know until it was checked.

Jim Sinclair may believe no one cons these guys but who says they got conned. Maybe they paid less for the fake bars and are part of the con. Plausible deniability. Even if some percent was discovered to be fake now there would be no proof the bars weren't tampered with after purchase.

Bitcoin doesn't suffer from all these problems. It has some of it's own but at least the math is math.

Someone needs to accept this challenge, fire up Vanitygen, and generate a bunch of 1tungsten addresses to fill Bitcoin with!

You are right. My apologies. Tungsten is .25% lighter than gold, not heavier, and so whatever you mix with tungsten to get the density of gold would have to be denser than gold, not lighter. Platinum would be the cheapest and most obtainable thing to use to mix with tungsten to match gold's density.

19.25W + 21.45P = 19.3 where W is cubic centimeters of tungsten and P is ccs of platinum.

W+P = 1 where we're looking for 1 cc

Solving these two equations gives us P = .02272727. .  ccs of platinum and W = .97727 ccs of tungsten

So, if you're having 1 cc of this fake gold, it would be made up of .97727 ccs of tungsten with a mass of 18.8125g, and .02272727ccs of platinum with a mass of .4875g.

18.8125+.4875 = 19.30, exactly what one cc of gold would weigh.

That's possible, but iridium market is so small and the annual production is so tiny, for any mass production purpose, it would push iridium price sky high in a short time, plus it will will draw much suspicion to the big iridium buyer. Platinum is the best choice.

Right, so when is someone going to IPO a fake gold-bars for bitcoins company? Looks like some fat profits to be had!

Not really an issue with GoldMoney because they ultrasound test every bar (http://www.goldmoney.com/gold-testing.html) before it goes into the vault. Any abnormalities get melted down and recast. Any tungsten and they get indemnified by the previous holder in the LBMA chain of custody.

But I do agree that verifying the quantity and quality of bitcoins is able to be done with much greater efficiency and cost effectiveness (only a few seconds of time).

btw, how do we know this wasn't a manufacturing accident and a bunch of people got incandescent light bulbs with gold coils?  ;D

I assume you are joking, but there are two obvious indications it is a deliberate scam:

• The colour is all wrong. As is the hardness. People on the manufacturing floor would catch such an error.
• Making a brick out of composite materials instead of a single material takes at least one more pour. You can't do that by accident.

Plus, gold wire bulb would not work, the wire would melt almost immediately. But, good joke.

My guess would be vaporize: gold has less resistance, implying higher start-up current.

Maybe Tungsten should become the official metal of physical bitcoins.

But tungsten melts at like 130 Fahrenheit or something and my GPU melts at like 195 Fahrenheit.  That'd be a significant downgrade.  Although, my hard drive that contains my live wallet copy probably fails at a lower operating temperature :P

It should be bronze so we can both throw it at someone for significant damage if they make fun of bitcoins and also get like $4 a pound USD at a scrap place if anything happens to the BTC system, rofl.

P.S. the gold would so work!  It wouldn't emit light but it's such a great conductor, I doubt it would melt because so much current can pass through it with so little resistance that produces heat.

Tungsten melting point 6,191° F (3,422° C)

waaaaaait, then how do fake psychics do that bullshit spoon bending thing just by rubbing their fingers on the neck of the spoon to make it bend from slight friction heat?  I'm 99% sure those are tungsten spoons and that's kinda the trick that they're not steel.

Ah ok, I thought maybe you were overclocking your GPU kinda high to melt tungsten.

Ugh, I kid you not, there's a wikipedia article on spoon bending and non mention what metal is used (except a possible reference to a titantium nickel alloy of some sort but that doesn't sound right.) I must be mistaken.  Googling "tungsten spoon bending" seems to indicate that, lol.

P.S. my GPU runs on self-sustaining nuclear fusion in a magnetic containment area inside the heatsink so yeah, it melts tungsten lol :P

Now you have to worry about coins:

http://www.zerohedge.com/news/2012-09-24/get-your-fake-tungsten-filled-gold-coins-here

Man this gives me a lot of anxiety because I plan to buy back some bullion in the near future. How the hell can I unsure, without wasting a lot of money, that what I buy will be real?

Run one through a bandsaw.

Now I'm wondering about fake silver.

Buy an ultrasound machine like the ones that dealers have, that's the only way to be sure. Otherwise, you can never be sure.

this si why I only get my gold from gold vending machines :P

http://www.zurichgoldtrader.com/gold-vending-machine-opens-in-abu-dhabi-hotel/

...and both of you are right to be worried:
http://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=silver+coins (http://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=silver+coins)

Best ad of the bunch: 

http://www.alibaba.com/product-gs/233194135/silver_coin.html

Someone actually attempted to sell me a fake silver morgan. Luckily I check all coins before I purchase. The coin was incredibly realistic. It was scary, especially since silver was only around $15.00 an oz. I wondered how is this remotely cost effective?? Then I did a bit of research and you could actually buy the fake coins for roughly $1.50 a coin, so yah it was actually incredibly profitable for the original scammer.

This reminds me of the guy who bought a UPS on trademe and wondered why it wasnt working. When he opened it up, there was a brick inside instead of a battery

http://www.popgive.com/2008/07/dont-buy-ups-without-warranty.html (http://www.popgive.com/2008/07/dont-buy-ups-without-warranty.html)

Haha wow, the lengths people will go to make a dishonest buck. Sad.

so i have access to an US that i'd like to use to scan my gold coins for integrity.  i was wondering if any of you guys know the velocity settings.  i captured this image off the Goldmoney video but see 2 different velocity settings that are quite far apart.  what do they mean and which one is the appropriate one?

https://i.imgur.com/f5uUG.jpg

The screen shows Velocity L and Velocity S.  If I had to guess, I'd say Velocity L (http://en.wikipedia.org/wiki/Love_wave) and Velocity S (http://en.wikipedia.org/wiki/S-wave)

Also, my understanding of waves in general suggests that one or more of those isn't a setting, but a measured parameter.

Sound wave velocity in tungsten is almost the double that of the gold, I don't know which kind of equipment is needed to measure them, but the difference is so relevant that I suppose it should be quite easy to spot.

Also, if suddendly a relevant percentage of gold held by bullions would be found false I suppose that would spike the gold price by quite a lot, since the real gold in circulation would be less that what was thought.

@ guy who wanted to use ultrasound to test metal (or anyone w/o access to $100k+ equipment:
you might be interested in this:
http://www.youtube.com/watch?v=_T8fdshyEek

and this (by the people who uploaded the youtube video):
http://about.ag/UltrasonicThicknessGauge.htm

So I'd like to ask the OP what it was that made him suspicious enough to risk cutting open a perfectly good bar? How did he know because I am not sure I would have been sure enough?

Next I would like to say that I am pretty sure that it would be quite a simple matter to measure the difference between filled and solid gold bars based on resistivity which would be a simple measurement to make in practice.

There are two key principles here - use a 4 terminal measuring device I would suggest that wooden or plastic block with contacts on the side and ends, could be used where the wooden block has an indentaion to match the exact size of gold bar. The principle of a 4 terminal resistance is that 2 terminals are used to inject a test current and 2 terminals used to read the voltage generated by this current. This cuts out completely voltage generated by poor contacts or leads.

Its not necessary to use a particularly large current - modern amplifiers are capable of accurately measuring very small offset voltages, and you are measuring a true differential voltage here that makes it a lot easier.

The last 'trick' which would add a little to the cost of what I have so far described a very simple cheap instrument, would be if it did in fact turn out to be too difficult to measure the offset voltage accurately due to offset noise in the amplifier. In this case you instead use an alternating current to perform the measurement and a synchronous decode to accurately measure the offset voltage. Such a decoder will reject all other frequencies including DC so that you only have the signal you want. I dont think this would be required, but it could be.

I can see that provided that you were happy to have an instrument that effectively only measured one size of gold bar, it would be very easy to devlop such an instrument. How could it be made more general purpose (to cater for many different sizes?). Not sure. To compare the same sized gold bar, its essential to have the contacts in the same place.

Indeed perhaps the hardest part (really) is that if I did this you'd have to loan me a few genuine bars to calibrate it! (As well as the fake!)

If there IS anyone who wants such an instrument I do actually have relevant experience to develop such a thing and am looking for work right now. Please PM me. It wont be cheap for a 1-off instrument, but it WILL work (I'd do a better feasibility study first. and it could save you a small fortune!! ) It would also be pretty interesting in that I have never heard of such an instrument but am pretty sure I could make one.

Drop the coins on a table and listen to the ringing sound. Tungsten should sound different. Also, I am 90% certain you can't press tungsten the way that gold coins are minted. It's very brittle and hard. So the fine details on these coins are probably going to look different than on real minted coins.

I would also like to hear from anyone who has seen these coins in person. I have my doubts.

uhhhh, skin effect?

That's only for AC of sufficiently high frequency, DC measurement should be fine.

I guess you are right...but good grief, how much current are we talking to saturate a bar?

IANAE but you don't "saturate" a bar. You apply a known voltage V and measure the current I, the resistance is R=V/I, you compare this against the resistance of a good gold bar (measured or calculated). You can do it with low current if you can measure things accurately enough.

Make a couple assumptions here, but from Wikipedia an average size of a Good Delivery gold bar is 250mmx70mmx35mm. The resistivity of gold is 22.14nOhm*m.
(22.14nOhm*m)*(.25m)/((0.07m)*(0.035m)) = 2259nOhm = 2.26uOhm

If you had a bar of the same dimensions that was tungsten covered with a 5mm layer of gold, the bar would have an end to end resistance of 3.44uOhm.

Something like this micrometer (http://www.home.agilent.com/en/pd-1000001296%3Aepsg%3Apro-pn-34420A/micro-ohm-meter?&cc=CA&lc=eng) should be able to measure the difference reasonably well.

Using low frequency AC and a 4 terminal resistance would work well, but there is an even better way to do this.

Use transformer with an airgap. (Operating around 50/60 Hz. Negligible skin effect at 50Hz.) A sheet of conducting metal inserted in the gap acts as shorted "turn" in the secondary of the transformer. The energy lost is detectable in the primary and is proprtional to the thickness of the metal and inversly so to its resistivity. So I believe that you could calibrate such an instrument in millimetres of gold and, well if it was actually mainly tungsten, then the reading would show as having a thickness of about one-fifth that observed in fact.

Certain assumptions need to be made about resistive and magnetic losses in the the core, the size of the airgap, the flux that does not go through the coin etc, but such an instrument could be made. It has to be designed correctly in short. And if it had an airgap 1cm by 1cm by 1cm this would allow its use on coins (there is a whole factory making fake tungsten gold coins in china, and has been for ten years so we have not seen the end of this!!) as well as 10oz bars. This seems to me much better than we previously discussed since it allows a measurement to be made without spiky contacts on your expensive polished gold bar, and it allows you to make a measurement even if you have not got a genuine bar to test against. You need a set of calipers and this instrument: thats all. In fact you can probably do it by eye anyway!! If your gold bar is 5mm thick and the instrument shows its thickness as 1mm, its tungsten!!

The most difficult part of the prototype is finding a suitable transformer type core that I can either hacksaw an airgap in. It needs to be laminated for low eddy-current loss at 50Hz.