Ceramic Tile as water enhancer?

[PapaBear]

I was thinking about nothing in particular while my wife was making a mosaic tabletop out of broken ceramic tiles and it occured to me that the clays used in the tiles are essentially the same as those used in Koi Clay and ceramics ie bakki media. My thought was that they could possibly be used as an augment to a TT or other similar shower much as Oyster shell would. The only concern would be the mineral/metal additives used on the top surface for coloring the tile itself before it is glazed. Anyone have any experience on the colorants/glazes used when they are fired??? I know some pottery colorants are lead based but that is a slightly different process.

[mitten]

Without a lick of background or anything that can pass as knowledge about this let me toss out the half formed thought that ceramic glazes are usually metals, like copper and lead.

Any body know?

Only slightly related...a ceramics factory near here, now gone, used to sell off their oops material as driveway gravel. So, there were many driveways to be seen that looked like mosaics.

Mickey the windowman

[PapaBear]

That's pretty much the extent of my knowledge too. I remember that much from firing pottery 40 years ago in grade school. I just don't know if the heavy metals are used in floor tiles as well, or if other materials have been substituted because of environmental issues.