copper just for pennies?

What are, if any, effects of metals on the root systems or plants in general. For example silver or iron---- Could you use copper bb's as grow rocks?
or marbles?(glass/plastic) This may sound stupid but just looking for new designs.

bump?

copper will kill plants

i saw on hgtv one day they said if you line your garden with a thin rod of copper, it will keep out a few pests, i know slugs are one for sure....might be useful on an outdoor grow...

unless you're an expert grower already, i wouldn't deviate too far from tried and true methods when starting to grow.

If you're already an expert - go for it and let us know how it works.