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  3. 18K Green Gold (electrum)

* 18K gold

18K Green Gold (electrum): what it's made of, its purity, and its value

Pale greenish tint from high silver / no copper. Rare; used as accent in multi-color gold pieces.

Published May 30, 2026

Quick facts

Karat
18K
Purity
75.0%
Fineness
750/1000
Color
Green
Density
15.6 g/cm³
Melting point
1010 °C

What it's made of

Gold
75%
Silver
25%

The gold content is fixed at 75.0% — that's what makes it 18K. The remaining metals are what set the color: Silver with little or no copper shifts the tone toward a pale green (this alloy is historically called electrum).

About 18K Green Gold (electrum)

Pale greenish tint from high silver / no copper. Rare; used as accent in multi-color gold pieces.

How much it's worth

The melt value of a 18K Green Gold (electrum) piece is gold spot price × 0.750 × weight (g), because only 75.0% of the metal is gold. A buyer then deducts roughly 5–15% for refining and margin, so a cash offer lands just under that figure. Higher-karat gold packs in more gold per gram, so it carries a higher melt value — but it's also softer and scratches more easily, which is why everyday jewelry often uses lower karats.

* Frequently asked

FAQ

Q. How much gold is in 18K Green Gold (electrum)?
A. 75.0% by weight. 18K means 18 parts gold out of 24, which works out to 750/1000 fineness — the rest is alloy metals added for color and durability.
Q. Is 18K Green Gold (electrum) real gold?
A. Yes. 18K is genuine gold — it's 75.0% pure gold by weight, alloyed with other metals. It is not gold-plated or gold-filled; the gold runs all the way through.
Q. Why is 18K Green Gold (electrum) green?
A. The color comes from the metals mixed with the gold. Silver with little or no copper shifts the tone toward a pale green (this alloy is historically called electrum).
Q. Will 18K Green Gold (electrum) tarnish or cause skin reactions?
A. Solid 18K gold doesn't tarnish, and skin reactions are rare for nickel-free alloys. Surface films usually come from skin oils or lotions and wipe off with a soft cloth.

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