1. Does gold have white highlights?
Cut the gold bars or jewelry with scissors, and observe the section with a magnifying glass. If you see white bright spots, because gold and iridium can't blend together, it means that gold is doped with iridium.
Step 2 measure specific gravity
First, measure the weight of a pure gold bar with a balance, then put the gold bar into a measuring cup and pour water to drown it. Then put the detected gold bars into a measuring cup and observe whether the scale of water rises or falls. As long as there is a change, it means that gold bars are not pure gold. But if it is gold jewelry, this method is not applicable, because there is air in gold jewelry.
Real gold is not afraid of fire.
Put gold bars or gold jewelry on the fire for a period of time and observe its changes. Because iridium will combine with oxygen in the air to produce oxidation reaction, gold bars with insufficient purity will turn gray; And pure gold will appear bright red after being baked by fire. However, this method may have some damage to jewelry.
Extended data:
Matters needing attention in buying gold ornaments
1, both soft and hard
The higher the fineness of gold jewelry, the softer it is and the less elastic it is. Real gold will have faint traces when bitten by teeth or scratched by needles, and will not change color when broken by hand. The low-quality fake is the opposite.
Step 2 identify colors
As the saying goes, gold is "seven green, eight yellow, nine purple and ten red", showing different colors due to different types and components of impurities. Experts believe that 70% of jewelry with gold is yellow with blue, 80% is yellow with gold, 90% is yellow with purple, and 100% is red with gold.
3, check the seal marking method
Gold ornaments produced by regular manufacturers are all printed with gold content and manufacturer's logo, such as 24K, 14K, etc.
References:
Baidu encyclopedia-gold