* K18: This indicates that the jewelry is made of 18 karat gold. 18 karat gold is a gold alloy that contains 75% pure gold and 25% other metals.
* HN: This is likely a maker's mark or manufacturer's mark. It identifies the specific company or individual who made the jewelry.
To determine the exact meaning of "HN", you would need to research the maker's marks for jewelry manufacturers. You can find information on maker's marks through resources like:
* Online databases: Websites like Gemological Institute of America (GIA) or the British Hallmarking Council often have databases of maker's marks.
* Books and guides: There are books dedicated to identifying maker's marks for jewelry.
* Antiques experts: An antiques dealer or jewelry appraiser might be able to identify the mark.
By researching the "HN" hallmark, you can learn more about the origin and history of your jewelry.