Glazed earthenware, glazed stoneware, soft paste porcelain and bone china
Although glaze will provide a barrier to liquids, earthenware, soft paste porcelain and bone china are porous and glaze imperfections are common but may not be obvious, so take a cautious approach to cleaning.
1. Use a cotton wool swab (on a cocktail or bamboo stick) dampened with warm water that has had a little detergent added (about one drop of detergent per litre of water)
2. Roll the swab lightly over the surface, don't wipe or scrub. Make sure your swab is always clean - change it if you see any dirt on it. Using a dirty swab will leave dirt behind in the cracks
3. When the surface is clean, wipe over again with water (to remove any detergent residues)
4. Blot dry with a paper towel