New Nero Marquina Alexander Black is an acid-sensitive limestone. Wine, lemon juice, vinegar, cola, sanitary cleaners or descalers leave etch marks on the polished surface — visible as matt shadows or a loss of gloss. On black polished stone, reaction marks and matt patches stand out particularly clearly.
For all applications an impregnation on a silane or polysiloxane basis is mandatory. It prevents water, oil and colourants from penetrating and reduces staining — but it does not remove the acid sensitivity. On polished surfaces we recommend refreshing the impregnation every 1-2 years.
Day-to-day care is carried out with a pH-neutral natural stone cleaner and a soft microfibre cloth. On dark surfaces you should not work too wet and should take residues off cleanly and dry, so that no streaks form. Avoid acidic cleaners, descalers and aggressive bathroom or kitchen chemicals.
Citrus, wine, coffee, oil and cosmetics should be removed promptly from horizontal surfaces. For heavily used kitchens a realistic expectation is important — the material is decoratively strong, but not as secure in everyday use as black granite.
For permanently weathered exterior surfaces the material is not suitable.