* gold-alloy-modifier hallmark
The GG hallmark: meaning, purity & value
Green gold modifier. Gold alloyed with high silver content and no copper for a pale greenish tint. Rare in jewelry; used for artistic effect in multi-color gold pieces. Historically referred to as 'electrum' in antiquity.
Published May 30, 2026
Quick facts
- Metal
- gold-alloy-modifier
- Common regions
- international
Stamps that mean the same thing
This purity may be struck into jewelry as any of: GG / GREEN GOLD / Or Vert / ELECTRUM. The mark differs by country and era, but the metal content is identical.
What GG tells you
Green gold modifier. Gold alloyed with high silver content and no copper for a pale greenish tint. Rare in jewelry; used for artistic effect in multi-color gold pieces. Historically referred to as 'electrum' in antiquity.
How to check it yourself
- Examine the stamp under a 10× loupe — genuine marks are crisp and evenly struck, not doubled or smeared.
- Confirm the mark reads GG or an equivalent such as GREEN GOLD.
- Photograph it in the Jewelry Identifier app to read the metal, hallmark, and any gemstones from the image.
- For a binding result, have an assay office or gemological lab run an XRF purity test.
* Frequently asked
FAQ
- Q. Is GG the same as GREEN GOLD?
- A. Yes. GG, GREEN GOLD, Or Vert, ELECTRUM all denote the same material — gold-alloy-modifier. Different markets and eras stamp it differently, but the purity is identical.
- Q. How do I confirm a GG stamp is genuine?
- A. Look at the mark under 10× magnification for crisp, even strikes, cross-check the weight-to-volume ratio against the expected density, scan it with the Jewelry Identifier app, and — when it matters — have an XRF test done by an assay office or gemological lab.
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