Can black spots on porcelain be removed by "eraser"?
There is a question asked Pottery Clay whether we can use eraser to erase black stain on ceramics. Actually, it is not recommended to use eraser with ceramics. There is a particular technique to remove stain on ceramics. Failing to do so might affect the beauty of the work.
Before cleaning, consider how tough the stain is and what it is. In case of the hard stain,
use cotton with water and vinegar to wipe on the stain. Wipe the ceramics with dry cotton again. For tough stain,
use Hydrogen Peroxide to remove it.
For stained grout, mix 10% of bleach with 90% of water and wipe the stain. If it doesn’t work, mix 25% of bleach with 75% of baking soda. Don’t forget to test the mixture on the small area of the ceramic first.
Pottery both glazed and unglazed might be dirty with dust. It is easy to clean the unglazed pottery by mixing water and lime juice and clean inside and outside of the pottery.
The glazed pottery can be clean by using soapy water. Wipe the pottery with water-soaked cotton again.