Frequently Asked Questions | Goldanalytix
Here you find answers to the most frequently asked questions on all topics related to precious metal testing. The questions and answers are neatly arranged according to key topics - so you can find what you are looking for very quickly.
Yes, gold has a density of 19.32 g/cm³, but the popular counterfeit material wolfram has a density of 19.30 g/cm³. For silver, which has a density of 10.49 g/cm³, lead-tin or molybdenum alloys with a similar density are often used. Thus, a counterfeit cannot be ruled out with a density measurement alone.
Basically, density can be calculated by dividing the mass of an object by its volume.
If you have the DensityScreenScale or the bar testing set GAX1000, then you can use our calculation tool for this. To do this, measure the weight in air and the weight in water with the density scale. You can enter these two values into the tool and it will give you the density. In addition, with the calculation tool you have comparative values of some alloys and many pure metals.
If you want to calculate the density yourself, the formula is:
Density [g/cm³] = Air value [g] / (Air value [g] - Water value [g])
We suggest that you repeat the measurement. Before a second measurement, please follow the steps below:
- Check that all components of the density measurement assembly are firmly seated on the scale and correctly arranged.
- If a completely unexpected result appears, restart the device and wait a few minutes.
- Carefully dry all components that should not be in contact with the water bath.
Now the scale should give you a valid result.
In addition, it may be that there are cavities in the material that are not visible from the outside or that the object is more porous on the inside than it appears from the outside. Also not expected contamination with denser or less dense materials/substances can be responsible for a wrong answer.
If you have any further questions, please do not hesitate to contact us.
- With experience it takes about 30 seconds to take a measurement and calculate the result.
- Make sure that the scale is located as steady and vibration-proof as possible.
- Ideally, start the device 5-10 minutes before you use it so that it can regulate itself.
- The density scale works most reliably in a stable environment with a room temperature of 20-25 °C. The most important thing is that the temperature remains constant during the time of operation or use.
- Also note that you cannot use the density scale to measure jewellery set with precious stones, as stones falsify the density. Also, do not weigh any substances that react with water, e.g. sodium or potassium, or have a water-soluble layer.
- The test specimen must be dry and clean.
- Remove any capsules and blisters before measuring, otherwise the result will be inconclusive.
- With weakly wetting liquids (e.g. normal water), air bubbles may accumulate on the carrier or the test piece. An air bubble with a diameter of 2 mm already causes a measurement inaccuracy of 4 mg.
The density scale only indicates the weight of the test piece in the water. To calculate the density, you need the normal weight of the piece and the weight of the object in the water. To free you from having to do your own calculations, we provide you with our Excel calculation tool, which does the maths for you. Simply enter your measured values and the density of your piece is calculated.
The measuring range of the density scale goes from 0.01 - 2000 grams. This means you can measure small objects as well as bars up to a weight of 2 kg.
Caution: With silver bars over 1 kilogram, the measuring basket may not be large enough, as silver has a lower density than gold and is therefore larger for the same weight.