How to dislodge / remove oil from this granite sur

Dear Sir,

We had sealed  polished Granite (http://tanbrown.org) (dark brown / grey) with water based
penetrating sealer.
As the Granite (http://tanbrown.org) was really porous, it took in 4 coats. It was allowed to
cure for 4 days. Thereafter
we put ink / oil to test the surface. The same was left on it for 2 days.
When we cleaned the
the surface with neutral pH cleaner. The ink came off 80% and (http://maplered.com) the oil
seemed to have penetrated as the surface looked darkened.

The question is  :   How to dislodge / remove oil from this Granite (http://tanbrown.org) surface ?

I look forward to your reply.

M. Jhaveri