Greek coin, Zeus Head?

Hi colleagues,

I need your help. I have a coin that resembles an ancient Greek one, but I can’t identify it. I couldn’t find anything like it in any catalog. The coin’s parameters are as follows: diameter 18 mm, thickness 3 mm, and weight 4.74 grams. Bronze.

I would appreciate any assistance you can offer.

Thank you in advance!
 

Rotating 180 degrees, the text on the bottom reads ΟΛΒ, which points towards Olbia, and towards a similar design on this:

https://www.acsearch.info/search.html?term=OLBIA&category=1-2&lot=&date_from=&date_to=&thesaurus=1&images=1&en=1&de=1&fr=1&it=1&es=1&ot=1¤cy=usd&order=0#:~:text=https%3A//www.acsearch.info/search.html%3Fid%3D12483492

I can't say much more as I know little about the pre-Roman period but maybe it is a helpful lead.

https://www.acsearch.info/search.html?id=1039148

Thank you. I found it!!!

I’ve checked the Numista catalog, and this coin doesn’t appear to be listed. All the similar coins I found there are larger, with diameters of 21-24mm and weights of 8-12g. 

Would it be appropriate for me to create a new page for this coin? I’ve never done that before, so I’d appreciate any guidance.

Thanks in advance!