Gold Testing Using Acid
The acid testing method for gold is one of the most cost-effective and straightforward techniques available. The procedure can be carried out as follows:
- Utilize the piece of gold you wish to test to scratch a touchstone, which is a black stone used for gold analysis.
- Use a genuine gold piece with the same carat as the item being tested to scratch the touchstone.
- Apply a drop of the acid solution to both scratches and compare the reactions that occur.
Density Testing
We can leverage our understanding of the chemical properties of genuine gold, such as its density, to verify gold items by following these steps:
- Pour a specific volume of water into a graduated cylinder and record the initial water level.
- Carefully place the gold piece to be tested into the graduated cylinder, ensuring no water spills over.
- Record the new water level in the graduated cylinder.
- Calculate the volume of the gold piece by subtracting the initial water volume from the new water volume.
- Dry the gold piece and weigh it on a high-precision scale to determine its mass in grams.
- Calculate the density of the gold piece by dividing the mass (in grams) by the volume (in milliliters).
- Compare the result to the known density of gold, which is 19.32 grams per milliliter. If the result is very close, the piece is likely genuine; otherwise, it may be counterfeit.
Differentiating Between Real Gold and Pyrite
Pyrite, often referred to as “fool’s gold,” is a shiny mineral composed of sulfur and iron. Many people mistakenly confuse it with genuine gold. Here are some ways to distinguish between the two:
- Magnifying Glass Examination: Real gold typically appears as a solid piece or consists of very thin sheets. In contrast, pyrite forms in crystalline structures that can be hexagonal, octagonal, or dodecahedral in shape.
- Hardness: Gold is malleable and can be scratched easily. When hammered, it flattens without breaking. Pyrite, however, is harder and will produce sparks when struck.
- Odor: Genuine gold is odorless, while pyrite has a distinctive smell reminiscent of rotten eggs or sulfur.