Onyx is a glossy, porous material that requires special handling and gentle cleaning. Remove dirt, grime and grease from onyx without damaging it. To clean your onyx surfaces with this technique, you need soft cloths, a towel, mild dish soap, warm water and stone cleaner. It takes roughly 15 minutes to clean the stone and six hours for the sealant to harden.
Wash the onyx with warm water and mild soap
Wet a cloth in warm water, apply a dot of liquid soap and wipe the onyx. This removes surface dirt, dust and chemical residue. Immerse the cloth in warm water and wipe the onyx to remove lingering soap.
Dry the onyx with a soft towel
Wipe the onyx thoroughly with a soft, dry towel. Buff it until it is completely dry.
Apply stone cleaner
Squeeze a dot of stone cleaner onto a clean cloth and rub it over the onyx for five minutes. The cleaner seals the onyx and protects it from grime. Let the cleaner dry for another five minutes, then polish the onyx with a soft, clean cloth. Buff it for 10 minutes using small circular motions.
Rest the onyx for six hours
Let the freshly buffed onyx rest for at least six hours before touching it with bare hands or getting it wet.