The most commonly used metal is copper in these cases. Most Etruscan jewelry is 18 karat gold but it varies - going as low as 15 karat. While pure gold is 24 karat, 18 and 15 karat gold benefit from their alloys. 18 karat gold is much more durable and harder than 24, and 15 karat is so much more durable and 'hard' than 18 karat. Some jewelry of the Regolini-Galassi tomb was too; thin, delicate and big to have been worn while more robust and less poutre gold ornamentation was solid enough to have been worn in life.