The silver content is different
1, 925 silver
Silver 925 refers to bai silver with a silver content of about 92.5%. The purity of silver at about 92.5% is regarded as pure silver.
Because the highly pure silver is soft and easily oxidized, 925 silver is added with 7.5% of other metals, giving it an ideal hardness.
925 pure silver is the international standard silver for silver ornaments.
2, sterling silver,
Pure silver is the metallic silver with a content close to 100%.
Silver is not active in chemistry, but because silver and sulfur have a special affinity, in the air can slowly produce silver sulfide and make it black, silver impure.
And silver in nature is easy to mix with platinum and other metals, so the life of "pure silver" generally refers to the content of 99.99% of silver or 92.5% of 925 pure silver.