While it is generally accepted that tiles are a very durable and long lasting surface, metallic finishes are not protected by a glazed surface and therefore can become damaged.
Gold is a very soft metal, and when applied onto a tile surface, it can be easily damaged by abrasives and harsh cleaners. Silver is also a soft metal.
Many other finishes are more durable, but still susceptible to damage or wearing off when attacked by harsh cleaners.
Treat these tiles correctly, however, and there will be no problems.
Once the tiles are installed, if the plating is damaged or wears off, there are only two choices available.
Neither the factory, nor Beaumont Tiles will entertain a claim against worn metallic surfaces on tiles.