If there is a black silver film on the surface, 2 grams of salt, 7 grams of baking soda, 8 grams of bleaching powder and 60 ml of clear water can be used to make a "gold cleaner". Put the gold jewelry in a bowl, pour the detergent, take it out after 2 hours, rinse it with clear water (preferably not hard water), bury it in sawdust to dry, and then wipe it with a soft cloth.

In order to protect the luster of gold jewelry, a thin layer of nail polish can be coated on it. Ring inlaid with precious stones Roll a piece of cotton with popsicle or matchstick, soak it in the mixture of toilet water and glycerin, scrub the precious stones and their borders, and then polish the ring with flannel. Never scratch with sharp objects such as blades.

Extended data:

Distinguish adulteration

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.

2. Measure the 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.

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