German 800 silver locket

Hi guys, recently bought this huge locket in an auction. It's marked with the moon, crown and 800. It has a mirror, and a space for a photo and I've seen them online described as "slide mirrors". It's 6cm by 4.5cm and has an unusual clasp.
I'd love to know what the pattern on the outside is so I can do more research. Thanks

 

I'd call it reeds or grass.

 

Ditto. Looks 1960s-early 70s. In the mid 70s Germany began to use more sterling (925), although 800 was still used occasionally.

Dory, is there a mark before the moon? An initial maybe?

 

Thanks AJ, yes there are initials but I can't make them out. I only knew it was a loon and crown because I'm familiar with that mark. I'll see what I can come up with now, searching for reed/grass pattern.

 

Thanks OBB, I'll look into reed/grass.