Possibly Roman? [résolu]

I have almost no knowledge about ancients - almost everything that I collect is of a much more recent vintage. I was hoping one of the experts out there could at least start me off on the right Emperor (and make sure that I am looking in the correct country!)
I can take better photos if needed - these are just IPhone images with a decent magnifier held in front of the lens:

approx. 2.3 g, and either approx. 20.5mm or 17.5mm diameter - depending on where you measure
approx. 1.81 mm thick

Thanks!

This an Antoninianus , and the emperor is Gallienus.

Obv: GALLIENVS AVG
Rev: PROVID AVG I think.

http://www.wildwinds.com/

This is a awesome site (the best in my opinion for ancients) and it has a very good word search). I'll give you a link for future reference .

And your coin looks like this one : https://en.numista.com/catalogue/pieces50388.html

I am very impressed! I had gone to the Wildwinds site and tried to find a picture list of all the emperors, and searched the web for images based on word searches like "roman spiked crown", but I hadn't found the coin yet.
[Now I learned the proper words would have been "radiate crown". I wish there was a picture book of proper search terminology...]
That sure looks like him! Thank you so much!

It's not the looks , it's the inscription that gave me the definitive answer . If you would go and look for all the coins that have a radiate bust...well , you would waste weeks because there are about 135789864 of them .

The good thing about roman coins is the fact that the romans had the latin alphabet , and the inscriptions are quite easy to read (for coins that are not to worn of course ) . They use Greek letters only for mintmarks and provincial coins .

I was seeing "G(unknown)LLI(E or H)(N or M)V"
You are very good at this!

Naaaah...There are a lot more people better than me . I just have a trained eye . Still consider myself a noob