Sir Henry Englefield was a mathematician, chemist, scholar and antiquarian who issued tokens in the early 1800's. This thick farthing size token was struck from a pellet rather than a flan to simulate an ancient coin. Englefield's bust in on the obverse, but I have no idea what the reverse inscription (other than the HCE monogram) means.
Interesting item! The A(Psi)NB is the year 1752 in Greek numbers, Sir Henry was born that year and died 1822. The A (Omega)IZ is the year 1817, the item was probably struck then. Greek numerals: http://en.wikipedia.org/wiki/Greek_numerals
