Shapur I identification help

[Marius]

Hello friends,
I know very little about Persian coinage but I do have one coin of Shapur-I. I find him very interesting, and it goes well with my collection of AD251-253.  Could someone help me identify the coin, and explain the imagery here?  Also, if anyone knows good internet sites or books about Shapurs multiple invasions into Roman territory, I would much appreciate hearing what you know.  I have read and enjoyed one article on the which might be good for other list members:

http://ddc.aub.edu.lb/projects/archaeology/berytus-back/berytus08/17.html

Thank you, and best regards,
Richard

[mashya]

woow thats a very nice coin could u give us the size of the coin.

[Marius]

Hi Mashya,
Thank you.  The coin is about 24mm wide, very thin, and 4.3 grams. 
Best regards,
Richard

[mashya]

That is a beautiful coin

Gobl SN I/1 (plate II/23)

May i ask how much u purchased it for?
I want an approximate idea

[Marius]

Hi Mashya,
Thank you for the reference number.  I bought the coin for about $65.  I am interested in the period of 251-253 and the reign of Trebonianus, and Shapur's invasions of the Eastern emperor.  I had never bought a Persian coin before this one.
Best regards,
Richard