What does M0 or MB marking on gold jewelry mean?

M0 or MB marking on gold jewelry typically indicates the metal's purity. "M0" often refers to 0% gold, meaning the piece is not made of gold, while "MB" could denote a specific manufacturer's branding or a type of gold alloy. However, these markings can vary by region and manufacturer, so it's essential to verify with a jeweler for accurate identification. Always look for standard purity marks like 10K, 14K, or 18K for clear information on gold content.