All the Phoenician head pendants I've seen are core-formed, not moulded - like the one I'll attach that is in the NY Metropolitan Museum, which also appears to be intended to represent an African.

But I've seen a few that are mould-formed that apparently come from early Roman times. A couple, as I remember, are illustrated in one of the volumes of Whitehouse's books on Roman Glass in the Corning Museum. They are monochrome purple glass, but yours is in better condition. If it's authentic, it's very nice indeed.

Cheers,

Will