Gold Evaluation Methods: Is It Gold?

The Nature of Gold

  • Symbol: Au
  • Atomic number: 79
  • Atomic mass: 196.96655 amu
  • Number of protons/electrons: 79
  • Number of neutrons: 118
  • Melting point: 1,064.43°C (1,337.58°K, 1,947.97°F)
  • Boiling point: 2,807.0°C (3,80.15°K, 5,084.6°F)
  • Density @ 293°K: 19.32 grams per cubic centimeter
  • Crystal structure: cubic
  • oxidation states: +1, +3
Various methods of testing exist, however the most commonly used is the acid test. Not only does this process show if it is gold or gold plated, but also can tell the karat of the gold. There are two steps when conducting the acid test:

  • Test for Gold - A small obscure scratch is made on the item, and a small amount of nitric acid is applied. Depending on the composition, it will turn different colors.
  • Test for karat - The item is rubbed onto a special test stone, and again, a small amount of nitric acid is applied on the test stone. The color changes depending on the karat of gold.

How diamonds and precious stones are evaulated

We use the most advanced and proven methods of evaluation in the industry, including base diamond value and reselling value. Often the reselling value of jewelry is greater than the base value, and we pass on the benefits to you.