On how much value E duty payable?

We dont have excise registration, we procured excisable material from excise dealer bring it to my site, some structurals were changed on that we are not avail the credit of excise duty on purchases.  Now I want to send it for some job work by thired party.  Thired party is a Excise duty registered party and that item after job work is chargeble under excise duty.  Now we are sending material by DC copy.  On how much amount we are liable to pay excise duty?  Is it on Material + Value add or on value add only - pls advice urgent