Golden ring 585?, Green stain

Hello,
I have found this ring on flea market, it have stamp/mark 585 on it, but to be honest in person it doesn't really look like gold to me.
It also have on two spots big green stains.I know other metals that are mixed with gold can oxidate, and make gold discolor, but can it be this much green?
It also had some jewel/rock, that was missing.
Any thoughts about it, what are the chance it might be gold?

 

I see a raw\unfinished and unpolished ring... You may test the metal, it could be 14k...
The green can be a deposit from another piece tucked in same box.
Try to polish after a vinegar bath

 

See the difference on ring in this ad!
https://www.fintek.co.uk/machines/otec-mass-finishing/polishing-jewellery/

 

Thank you for your reply, I will try it out

 

Looks like an unfinished student's practice ring,possibly made of Merlin's gold/red brass.

 

Are you looking for more information? The ring never had a stone in it,you will need to get the metal tested for content.The 585 marks were applied before the inside of the ring shank was sanded and pre-polished.There is probably more but photos are just photos.

 

Lots of fake marked stuff being peddled lately. Just that the stamp is off is a hint it may not be legit.