Victorian 9K small locket

Well in my country you can't call 9K 'gold'. Here in Belgium we only recognise 14k onwards as real gold. I think thats a good rule. At least with 14K half of the material used is gold. So this way people don't get too dissapointed when they buy gold jewelry.
This locket has no hallmarks but it tested as 9K.
I bought it (its about 1cm diameter) on internet a few years ago. I think its from +/- 1880 or something. Its clearly been loved a lot. The pattern has worn off partially.
The front and the back look almost exactly the same, apart from the hinge on the front.
I like it how you almost can't see you can open it. It's like a hidden compartiment. I also have a similar one thats bigger. I love to wear this one with some charms on a necklace.