925 silver refers to silver products with a silver content of about 92.5% and a purity of about 92.5%, which is considered as pure silver. Because high-purity silver is soft and easy to be oxidized, 7.5% other metals are added to 925 silver to make it have ideal hardness. 925 sterling silver is the international standard silver for silver ornaments.

925 sterling silver is the international standard silver for silver ornaments. Printed silver ornaments are generally stamped with the English abbreviation of silver ("S" or "Sterling"). The mark of standard silver is S925. The imprint of foot silver is S990. But there are also many countries that don't print paper money on silver ornaments. Platinum (Pt for short), also known as platinum.

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925 silver is generally called standard silver and marked as "S925" or "Ag925". Because some other metals are added, it is not easy to deform and has enough brightness, so it will not turn black, but it cannot be reproduced. Common in fashion necklaces, rings, bracelets, earrings, etc.

990 silver is generally called pure silver and marked as "S990" or "Ag990". Its texture is soft, and rings and necklaces made of it are easy to deform or break, and also easy to turn black. The advantage is that it can be done again if it is broken. Common in traditional jewelry, bracelets, life locks and so on.

"925" silver contains 92.5% silver and 7.5% copper, and the jewelry is marked as 925. Most of our common silver ornaments are made of 925 silver. After polishing, 925 silver jewelry presents a very beautiful metallic luster, but also has a certain hardness, which can be inlaid with gems and made into high-grade jewelry.

Baidu Encyclopedia -925 Silver