Question about contact microphones

I'm making a sound installation where a contact microphone is rigged to a singing bowl and feeding the output to a speaker that should in theory excite the bowl by playing the same frequency into it, thereby making the bowl never stop playing.

The problem I'm running into is that the speaker creates a feedback loop with the contact mic, which I thought was impossible since the mic should essentially ignore the speaker output because it's not a vibration of the material it's stuck to.

Does anyone have any experience with this or another idea for making this work?

Thanks:)