Help needed to identify coin

I am looking for help identifying this coin, I have done some research into it but was unable to identify its origin, history, or value. I signed up to the forum earlier to post this question in the hope that someone could help identify it.

& src="https://en.numista.com/forum/images/miniatures/62c127e6afca4.jpg" src="https://en.numista.com/forum/images/miniatures/62c127ee6cc40.jpg">

known about the coin:

Metal - Silver (known from the magnet test)

Shape - Slightly oval

Alignment - 90°

Detentions (mm) - 

~⌀26 to ⌀29

~3⊔

Weight - 11g

Observations: 

1. Slightly converse on the obverse

2. Edge plain with slight pitting in the silver. 

Any help or information on the coins history or value or for places I could try looking for this information would be really helpful.

Thanks

HIGHER QUALITY IMAGES HERE https://imgur.com/a/8P9umGR
 

 Links 

https://en.numista.com/forum/images/62c127e6afca4.jpg 

https://en.numista.com/forum/images/62c127ee6cc40.jpg 

Pictures [cropped, rotated, white balanced] 

 [⌀26 to ⌀29 / 11g] 

Hello, this seems to be a Stater from Tarentum (Calabria), likely minted between 325 BC and 320 BC. The small picture of a dolphin on the obverse is a reference to a story in which a dolphin rescued the founder of Tarentum from a shipwreck. Because of this, many of their coins feature such dolphin.

I was unable to find an example of this coin in silver but I found one in gold that features the same design.

N#180242