Au is the symbol of gold, and G is gold (abbreviation of English gold). 750 is 75% gold. Thousands of pure gold (or pure gold) is also called 24K gold, which is about 4. 1K, so 4. 1666% *18 = 74.9988%, which is about 75%, commonly known as 750 or/. I don't know if that's what you're asking. If your physical object is the same as what is written on the guarantee, there will be no problem.