You need a terrazzo expert. Those aren't that numerous outside of FL. A stone restoration company might be your best lead to find someone who won't ruin it trying to restore it.

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You also need to have realistic expectations- terrazzo is cement and marble chips so it is porous- some stains simply will not come out. We restored a house that had been through a fire and the terrazzo was subsequently covered with vinyl tile. The Fange from the fire came off but there was still a ghost from the tile- probably twenty years of mop and glow soaked in.