I Had My Gallbadder Removed By Laproscopic Surgery. I Was

I had my gallbadder removed by laproscopic surgery. I was told there were clips present in the porta hepatis. I will have to have and MRI done in the near future. I need to know what those clips are made of. I do not want to have any problems arise when the MRI is done. I have tried finding out from various sources and noone seems to want to answer my question.