My boyfriend got me a gold engagement ring. He insists it's real gold but the ring keeps turning my finger green. Why?

Does a high gold K weight mean a harder or softer metal?

My gold ring is marked 585. What does that mean?

How can I turn silver colored jewelry gold?

What are grey gold alloys?

Where can I buy men's gold necklaces?

Is it true that yellow gold diamond engagement rings are out of style?

What is the difference between 14k and 24k gold?

What are the advantages of having my engagement band made out of yellow gold?

What are the advantages of having an engagement ring made out of white gold?