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Granite vs Slate

It may seem that there are endless options for hard surfaces in homes, businesses, and other areas. There are so many materials available for hard surfaces it can be dizzying for a consumer to think about which material to choose. But if the decision has been narrowed down to a choice between granite and slate this article may help. In this comparison of granite vs slate we will examine the properties, durability and uses for each of these natural stone materials. As we do, it should become clear which is right for the project you are considering.

Natural Granite - The Countertop Standard

For many years it seemed as though granite countertops were the go to surface for kitchens. The fact that so much attention was given to this surface meant that it had a favorable reputation with those who had owned it. Because of its success, granite seems to be the material against which all other materials are compared. Questions like, "is this material harder than granite?" and exclamations such as, "oh I like that countertop as much as the granite one we saw!" reveal that this material is the standard. That is not to say that granite is the only option or that it is the best option for every situation. It simply means that it is the material that many people are familiar with.

Surfaces Slated for Success

Even though natural slate is not as well-known as granite that doesn't mean it is without recognition. Slate surfaces are found in a number of places and the material is used for a variety of applications. Walkways, flooring, roof tiles, and countertops are all made from slate. Chalkboards were historically fashioned from the stone. Billiards tables are another use for the natural material. So just because granite is very well known, don't overlook this contender.

Comparing Slate and Granite

The first thing to keep in mind is that choosing materials does not have to be an either or choice. There are plenty of projects that use both of these natural stone materials. Rather, the idea here is to note the similarities and differences between these materials so that informed choices are made.

A Hard(ness) Look

The first aspect of comparison between slate and granite that we will look at is hardness. A surfaces hardness is what makes it scratch resistant. The scratch resistance of a stone makes it usable for surfaces that take a lot of abuse. For example flooring in high traffic areas must be scratch resistant to hold up under the weight and edges on shoes.

Both granite and slate are hard materials. Furthermore, both have been used for flooring, staircases, and walkways. Slate has a hardness of 5-6 on the Mohs scale of mineral hardness. Granite also is found in both of those hardness ranges and some even registers at 7. SO both of these materials are on the upper half of the range.

The Porosity of Granite vs Slate

Porosity is an important comparison when it comes to natural stone. The more porous the material is, the more liquid it absorbs in a shorter period of time. Granite is available in grades and the grade of the material affects the porosity of it. Slate on the other hand has low porosity and for this reason it is not uncommon to see it used as roofing tiles in some parts of the world.

The porosity of a material influences the frequency with which it needs to be sealed. Applying an effective natural stone sealer periodically slows the rate of absorption to help resist staining.

Slate vs Granite Colors

One of the big factors in choosing a stone material is the color selection. The more colors there are from which to choose, the more projects the material is compatible with. Let's delve into the comparison of color ranges now.

Granite is available in a large number of colors. Additionally, there are stone treatment products that enable you to enhance the color of stone and even dye the stone a different color.

Slate's color selection is not as broad as that of granite. It's range is somewhat limited and they are; gray, black, blue, and green. The shade of each stone will vary. The most common slate color is grayish-green.

Making the Choice

Choosing between granite and slate is going to depend on a few factors. First, the application may affect which material will be chosen. For example, you probably aren't going to see granite roof tiles. Even though granite is a durable material, the absorption rate would only add to its weight when it rained; as if it wasn't heavy enough. Second, the design and color scheme. If your project calls for a vibrant color serving as a surface on a focal point, then slate probably won't be the choice. You get the idea. The job itself will lend itself to a given material and lead you to the decision.

Comparison of Granite vs Slate
Property Granite Slate
Hardness (Mohs Scale) 5-7 5-6
Porosity Variable Low
Color Selection Wide Range of Color Gray, Black, Blue, Green
Needs Sealed Yes Yes

In the end, choosing between granite and slate will depend largely on what the design calls for and what the application is. However, there are a number of situations where either of these materials will suffice. In those cases the question will simply be, "which one do you prefer?"

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