10 ozt fake gold Bar
Last year a number of gold bars had been found that actually contained large percentages of tungsten in them. On 3/23/2012 a 1kg Metalor gold bar was found in the United Kingdom where gold was drilled out of its center and tungsten rods were inserted inside and it was resealed with gold. In September of 2012 ten 10 Troy ounce PAMP gold bars were found to have only a thin shell of gold around a tungsten core. There are also reports of tungsten laced 500g bars found coming from a Germany bank in 2010.
500 Gram Tungsten Filled Gold Bar
Tungsten trades for just over a dollar an ounce and almost has the same heft as gold. Tungsten is also not magnetic (it can’t be detected with a magnet). Its specific density (or gravity) is 19.600g/ml (ml=milliliter or 1/1,000 of a liter) this means 19.6 grams of tungsten will displace 1ml of water when submerged. This is very close to gold’s specific gravity which is 19.320g/ml. A 100g gold bar will displace 5.176ml of water and a 100g bar of tungsten will displace 5.102ml of water. There is only 0.074ml difference in volume between the two extremes. The one kilogram tainted gold bar was about 30% tungsten and 70% gold. A 100% 1kg gold bar has a volume of 51.76ml then a 70%/30% bar will have a volume of {(0.7x51.76)+(0.3x51.02)=} 51.54ml this is only a difference of 0.22ml displaced water. This discrepancy of (0.22/51.76=} 0.425% in volume can be very difficult to measure. Ultrasonic meters have been adapted in order to determine if there is tungsten hidden underneath a veneer of gold.
Outside of these limited occurrences in which pure gold is the overlay of tungsten there are a number of different ways to check whether a bar or coin is gold. A simple test is to use a strong magnet. Since gold is not magnetic if you bring the magnet to the bar or coin in question and the magnet ‘pulls’ towards the metal does not contain a significant amount of gold and may only be gold plated.
Gold Test Kit
There are gold test kits which have droppers of acids and a test stone. The different test solutions for gold and these will be labeled 10 karat, 14 karat, 18 karat, and 22 karat. Often when you buy these kits they will also include an acid solution for silver and one for platinum. Be careful with these testing solutions! They contain a corrosive acid. All directions should be read before using and gloves are recommended. Children under the age of 18 should not use these tests. The test stone is for rubbing off a little streak from the metal for testing with solution. You should start off with the 10-karat solution first.The idea is that if the drop of solution dissolves the metal the coin or bar has a gold contain lower than the solution is labeled as. That is if the metal streak disappears with a drop of the 10-karat solution then the coin or bar is lower than 10 karats. In the United States items with less than 10 karats can not be labeled as being gold. If the 10 and 14 karat solutions have no effect and the 18 karat does then the item is between 14 and 18 karat gold. The silver and platinum solutions react differently than the gold solutions.
A scale is highly recommended. Inexpensive digital scale can easily be found. You might want to find one that has a “Troy Ounce” unit selection for easy conversions. Digital calipers can also be found and can be useful in verifying coins are within their mintage dimensions. Knowing the weight of your bar or coin you can use gold’s specific density (sometime called specific gravity) you can determine if it is true to its indicated fineness.
As far as listings be aware to avoid those with the labels of “mils or mills”. These refer the thickness of plating and not for the purity of the bar or coin. For example; "99.99% fine gold 100 mills plated copper bar." Means the 100mills gold platting is 99.99% gold and the rest of the bar is copper.
