Pewter (?) item w/ head of Constantine I (assumed) & rampant lion

[gwdigger]

Found this on a mid to late 18th century homesite in Maryland. Any ideas what it is or from? Corroded but neat display item. At 1st sight I thought I had a roman coin but its clearly not.

 

[CRUSADER]

I agree the head looks like Constantine I, no idea why you would mix it with the Lion??

 

[gwdigger]

Me either. An oddball.