Sealing
Marble, limestone and travertine are porous and should be sealed on installation, then resealed every twelve to eighteen months in a kitchen or bathroom. A penetrating sealer sits below the surface and does not change the finish. Ask your stonemason which product they have used, because reapplication should match it.
Granite and quartzite are denser and often need sealing only every few years. Sintered stone, porcelain and solid surface do not need sealing at all.
Everyday cleaning
Warm water and a pH-neutral cleaner, then dry with a soft cloth. Avoid anything acidic, including vinegar, lemon, and most bathroom and tile cleaners: acid etches calcium-based stone, leaving a dull mark that no amount of cleaning removes.
Wipe spills of wine, oil, citrus and coffee straight away. A stain that has soaked in needs a poultice, not a stronger cleaner.
Stains and etching
A stain is colour that has soaked into the stone. An etch is a change in surface sheen where acid has dissolved a little of the stone. They are treated differently.
- Oil, grease and cosmetics: a poultice of baking soda and water, or a proprietary oil poultice, left under plastic for 24 hours.
- Wine, coffee, tea and food colour: a poultice with 12 per cent hydrogen peroxide.
- Rust: a stone-specific rust remover only. Never acid.
- Etch marks on polished marble: light marks can be buffed with a marble polishing powder; deep marks need re-honing by a stonemason.
Outdoor stone
Bluestone, granite, sandstone and outdoor sintered sheets need little more than a hose and a soft brush. Use an outdoor stone sealer on sandstone and porous limestone in areas that stay damp, and never a pressure washer on sandstone: it opens the surface and accelerates weathering.