While you can cut directly on some stone countertops, it is not recommended.

Granite is one of the most durable countertop materials you can buy, and it can certainly withstand cuts from a knife blade. However, if your granite has a sealer on it, cutting can eventually wear down the sealant. Over time, this can lead to liquids and food absorbing into the stone, which can cause stains and other issues that require repair.

With unsealed granite, cutting may be be less of an issue, though again not suggested. Generally the stone is hard enough to be cut on without scratching, however it is also hard enough to dull your knife blades rather quickly.

Similarly, quartz is a very durable, scratch resistant countertop that in most cases can be cut on without damaging the stone. Quartz is not completely scratch proof though, so it is still possible to cause some damage. 

Other natural stones are softer and are more likely to scratch if a knife is used on the surface. Marble, limestone and sandstone are among these. Many of these stones also require a sealer, which again can be damaged and lead to scratches and stains. Soapstone is a softer stone that scratches quite easily, however it can be restored with mineral oil or by sanding.

While it is possible to cut directly on natural stone, it's generally safer and easier in the long run to use a cutting board.  

Most granite is very stain resistant and does not “require” sealing. However, sealing is an added precaution, and many fabricators and installers do recommend it. Quality Granite & Marble typically makes this determination, and applies sealer when needed.

A general rule used when manufacturing is, if water darkens the stone, it needs a sealer.

It’s important to know a little about the granite slab fabrication process before sealing. Resin coating applies an epoxy over the stone slabs. This resin fills the voids, veins, and fissures. This process was developed to make unstable stone sellable. The more the process was used, the more common it became. Many fabricators simply apply resin coating to all slabs to keep things simple. When you mix a sealer with an unknown resin, it may turn the resin cloudy. This is one reason you may not want to blindly apply a sealer. Check with your installer first.

For stones that do require, or would benefit from, sealing, there are a few variables to considers when determining how often new sealer is needed.

• How much abuse the countertop gets
• How often the granite is cleaned
• How absorbent (porous) the natural stone is
• The type and quality of the previous sealer used

Many sealers applied at the factory last 10-15 years, while store bought (DIY) sealers may only be good for 6-12 months. So it’s important to know if you had a sealer before, and what type.

A simple water test will help you determine if sealer is needed. Pour about a quarter cup of water on a few areas of the counter. See how long it takes for the water to absorb. If the water absorbs into the stone in less than five minutes, the stone does need to be sealed. If the water is still standing after 30 minutes, no sealer is needed. Anywhere in between five and 30 minutes, the stone may benefit a sealer.

Sealing granite is a relatively simple process and can be done by a professional or by homeowners. Before sealing, it is important to know the makeup of your stone, so check with your fabricator and/or installation documentation to make sure you select the correct product and sealing process. If you have questions about how often you should seal your granite, call us at 316-946-0530.