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Mikimoto
Mikimoto shell-and-M emblem above 750: maker device and gold fineness are separate parts of the mark.
Read the stamp
750 gold stamp
750 is the gold fineness mark for 750 parts per thousand, or 75% gold, equivalent to 18K or 18CT. Yellow, rose and white gold can all carry it because the number measures gold content rather than colour.
750, 18K, 18CT and Au750
The calculation is exact: 18 parts gold out of 24 equals 75%, or 750 parts per thousand. The remaining 25% consists of other alloying metals. An 18K 750 stamp repeats the same fineness in two systems, rather than adding two grades together. Au750 uses the chemical symbol Au for gold before the same numerical standard. These marks describe an alloy, so 750 does not mean pure, 24-karat gold.
Why a silver-coloured ring can say 750
White gold can have the same gold content as yellow or rose gold. Changing the other metals in the alloy changes its colour without changing the 750 gold standard. A pale 750-stamped piece can therefore be 18K white gold. Cartier describes its white, rose and yellow gold as 750/1000. Compare the complete hallmark and product description when distinguishing white gold from silver or platinum: the surface colour is not a fineness scale.
The maker and country are separate clues
Inspect the inside of a ring, the back of a pendant, or the clasp and end fittings of a chain. Keep the maker’s initials or name, country wording and numerical marks together in a photograph. ITALY beside 750 supplies origin wording, not a different gold percentage. The number 750 is used by many makers and is not a brand signature. In a full UK hallmark, separate punches identify the sponsor, the metal standard and the assay office.
18K gold versus an 18K surface layer
A plated object can have an 18K gold surface without being an 18K alloy throughout. GP means gold plated; GF means gold filled, with a mechanically bonded gold-alloy layer. HGE describes heavy gold electroplate. Retain these letters with the karat number when reading a stamp. UK gold-plated silver is hallmarked as silver, and standalone 18K or 750 marks are not permitted as an extra gold-purity stamp on it. The wording 18ct gold plated silver describes the construction instead.
What a doubtful 750 stamp needs
A lone number is the claimed fineness, while a full hallmark supplies additional identity and assay information. Counterfeit jewelry may carry generic numbers and symbols. When a worn stamp or mismatched marks raise a question, examine the complete object and have the metal checked rather than choosing from its colour. On pieces with multiple components, keep each visible mark attached to the component where it was found.
Examples
Frequently asked questions
What does 750 mean on jewelry?
As a gold fineness mark, it means 75% gold, the same proportion as 18-karat gold.
What does Au750 mean on jewelry?
Au is the chemical symbol for gold; 750 means 750 parts gold per thousand, or 18K.
Does a 750 stamp on a silver-coloured ring mean silver?
White gold also carries 750. Read the complete hallmark and maker’s material description; the colour alone does not identify the metal.
Can a fake have a 750 gold stamp?
Yes. Generic numbers can be stamped onto counterfeit goods. A full hallmark and examination of the metal provide information beyond the number alone.