Minimum thickness for marble on a floor - Tile Advice

[Musivarius]

I have just had someone ask me if 4 mm thick marble is suitable for a floor. I've only ever used 10 mm thick, I assume 4 mm would be too thin? It's for a mosaic so they would be 10 mm x 10 mm x 4 mm. Thanks

 

[Old Mod]

Good to see you again Lawrence,
been a long time, trust you’re well.

Wouldn’t want to guess about 4mm thick marble mosaic, would have thought there’d be a good chance of it crushing under point loading.

 

[Musivarius]

Thanks, been away a while as I'm just mainly teaching now rather than looking for commissions, (whenever anyone asks me about technical stuff though I tell them, 'ask the technical people or tilers' but it never seems to work hence you get mosaic people still recommending PVA as a primer!)
They were looking to do their toilet so not major footfall but the suppliers are re sellers so they won't know and I can say I've heard of any being used for a floor.

 

[Old Mod]

Thanks, been away a while as I'm just mainly teaching now rather than looking for commissions, (whenever anyone asks me about technical stuff though I tell them, 'ask the technical people or tilers' but it never seems to work hence you get mosaic people still recommending PVA as a primer!)
They were looking to do their toilet so not major footfall but the suppliers are re sellers so they won't know and I can say I've heard of any being used for a floor.

Do you know the substrate Lawrence?

 

[One Day]

How thick were roman tessarae?
I don't see a problem with 4mm mosaics on a solid floor.

 

[Musivarius]

They have said the floor is levelled concrete, I am not sure if they were intending to set anything on top though. My usual reply to anyone getting material for a project is to say get a tiler to confirm the floor is suitable for whatever method they want to use.
Roman tesserae on the floors were 10 mm thick but they are quite a few instances were they were 20 - 30 mm thick, even with the same 10 mm along each side.

 

[Flintstone]

Only last year I was asked to use 1mm thick mother of pearl mosaics on a wet room tray. I refused, but somebody else did the job with them. I think the same as impish, can’t see a problem if they are solid bed on a solid floor

 

[Musivarius]

Thanks, that was my thought too.