Juan Carlos, I believe if you follow the bridge height screws into the body, you should be able to see them going into metal inserts in the body. I can't say for sure if this is standard construction spec across all Alembic instruments (Mica . . . . . ?), but I would be surprised IF yours is screwing directly into the top of the body.
Remember we're talking about polishing ONLY the unfinished parts here . . . so do NOT try and use a brass polish on clear-finish or plated parts (anything with a chrome or gold-plate or black finish). So generally we're talking about the bridge and adjustable nut on most, but not all, Alembics. If all of your hardware is gold or chrome or black plated, do NOT do this, as it can scuff the plated bits just like sandpapaer.
Also, on most Alembics, the tailpiece and the brass back cover plates are clear plated, so we don't want to brass polish these either.
Generally on plated parts (both of mine have gold tuning keys), a little automotive wax works well, JUST a little. And be sure you use wax, NOT wax-polish. In auto refinishing circles, wax is only wax: A polishing wax usually includes a bit of polishing compound, which again, can tend to act like fine sandpaper on finished parts, so be sure which one you're about to use.
BTW, a good wax is also a great guitar polish if you have clear gloss finish on your basses like me. I'm a huge Barry Meguiar fan (I'm Car Crazy!) so you can guess I'm not using Mother's . . . . Again, be sure it's wax and not polish.
The Eagle One Nev'r Dull is FAST on brass, but can leave quite a bit of black residue, so be sure you get it all off with a clean, dry rag. I also put rags under mine if I do it on the bass, can not get a good answer from Eagle One that it's as inert as the other things in my cleanup bucket, so Rusty has the right idea.
J o e y