How to Seal Granite Countertops, Marble and Dolomite (Printable Care Guide)
How to seal granite countertops: for granite, marble or dolomite, start with the water test: if a small puddle darkens the stone within about 15 minutes, it is time. Clean and dry the surface, apply a stone sealer made for natural stone following its label, let it soak in for the time listed, wipe off the excess and let it cure before heavy use. Quartz never needs sealing.
Summary
- The water test tells you when sealing is due.
- Clean, dry, apply, wait, wipe off excess, let it cure.
- Always follow the sealer label for times and coverage.
- Sealing prevents stains; it does not stop etching on marble.
When to Seal: The Water Test
Pour a coin-sized puddle of water on the stone near the sink and the range, the areas used most. Wait about 15 minutes, then wipe it off. If the stone darkened under the water, it is absorbing liquid and should be sealed. If it looks unchanged, check again in a few months.
How to Seal Natural Stone, Step by Step
- Clean: wash the counter with a pH-neutral stone cleaner and rinse.
- Dry: let the stone dry completely, ideally for several hours.
- Apply: spread a sealer made for natural stone in small sections.
- Wait: leave it on for the time the label recommends.
- Wipe: remove all excess with a clean, dry cloth before it gets tacky.
- Cure: avoid spills and heavy use for the curing time on the label.
Test the sealer on a small hidden area first, especially on honed or leathered finishes.
How Each Stone Behaves
| Material | Needs sealing? | Special note |
|---|---|---|
| Granite | Periodically | Dense granites may need it rarely |
| Quartzite | Periodically | Very hard but still natural stone |
| Marble | Periodically | Sealing doesn't prevent etching |
| Dolomite | Periodically | Wipe acids promptly |
| Quartz | Never | Non-porous; just clean it |
Printable Care Card
Print this section and keep it inside a cabinet door.
- Daily: warm water and mild dish soap, or a pH-neutral stone cleaner.
- Never: vinegar, lemon, bleach or abrasive pads on natural stone.
- Spills: wipe wine, oil, coffee and citrus right away.
- Heat: use trivets, especially on quartz.
- Sealing: do the water test once a year; seal when the stone darkens.
Living with marble? Read our guide on living with marble countertops, and for bathrooms, our guide on marble vs granite bathroom. See our marble slabs, or browse more countertop stone guides.
Frequently Asked Questions
How often should granite be sealed?
When the water test shows darkening. For many granites that is about once a year; some need it less.
Can I seal my countertops myself?
Yes. Follow the sealer label and test a hidden spot first.
Does quartz need sealing?
No. Quartz is non-porous and only needs cleaning.
Will sealing stop marble from etching?
No. Sealing prevents stains, not the reaction with acids.
What happens if I never seal granite?
It may absorb oils and develop dark spots, especially near the range and sink.
