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

How do I know if my gold jewelry is real gold or not? Is there any test I can do by myself?

What is the difference between white gold and yellow gold?

How is gold extracted from the earth?

What is the difference between 18K white gold and platinum? (Also, what's "better"?)

Is there such thing as black gold?

What does the "k" in gold rating (18k,24k,etc) stand for?

What's the value of a 18K gold men's bracelet?

What are the possible colors for gold? Which colors are naturally occurring and which ones are artificially created?

What is more shiny: Platinum, Palladium or White Gold?