Whose makers mark is this on silver earrings?

Hi everyone,

I picked up this pair of half hoop earrings which are stamped Ster and there is another mark on them too, any thoughts as to whom this belongs?

Also would you say these have opal in them, or is it something else?

TYIA for any help.

 

Bits of opal in clear resin or some such. I see Sterling, a copyright symbol, and a mark I can't read.

 

Thank you, good to know it is tiny slivers of opal (my birthstone, so that's a yay!)

Yes, it was the mark you are having trouble with that was also intriguing me. I wasn't sure if it was an animal head perhaps? But I don't think it is one I have had before so I am not sure.

 

Might be. I can't see it clearly enough to even guess.