Selecting Stone Types – What to Know
If you are looking for a new countertop surface or you have been looking for one, you may have asked yourself, “What is the difference between…”, when comparing to types of stone that look very similar but are called by different names. In this post, we are going to give you a high level overview of some of the different stone types and how they are different from each other. As we cover the differences, we will briefly cover some of the affects this can have on the fabrication and installment process. So, let’s begin exploring some of the stone types that you might run across in your search and what some of the differences are.
The first thing to consider is the two main categories of stone. These are very simple categories and may be different from category lists that can be found elsewhere on the Internet. Our two classifications are:
- Natural Stone
- Engineered Stone
These two main categories are somewhat basic and do not need a lot of explanation. Natural stone, as we define it, includes any stone slab that is the result of being mined out of the earth and cut. Engineered stone is, as you would expect, stone that comes from an engineering process of some sort. This engineering process can include a variety of procedures or tasks. The real key is that the process of forming the material is controlled by an engineering system, team, or both that causes the material to become what it is.
Now that we have clarified how we define the categories, let’s consider them one at a time.
In the realm of natural stone, there are a number of materials. They vary in composition, appearance, and hardness. The main aspects all affect how the stone material turns out. For example the hardness of the stone plays a role in its scratch resistance. The harder the stone, the more difficult it is to scratch. Some natural stone is softer and other is harder. Because of this variation, a scale of hardness exists to help convey somewhat accurately a stone’s hardness. This scale is known as the Mohs Scale of Mineral Hardness.
As stated above, appearance and composition also vary when it comes to natural stone. The composition may be made up of a variety of minerals and other matter. The variations in color, texture and hardness are a direct result of what material the stone contains. Depending on what minerals are in the stone, it will be declared a certain type of stone. Here are the more popular natural stone types:
These stone types are each unique. Although some of them may be similar, each has characteristics that distinguish it from the others. For example limestone and travertine are very similar but travertine has voids (a.k.a. holes or pits), that are very distinctive and differentiate it from limestone. These are the kinds of things that can help when you are searching for stone surfaces.
Natural Stone Care
One reason that these are good things to know is that it helps the owner of the stone to care for the surface in the proper way. Let’s look at another example that highlights this fact. Marble, limestone, travertine, and onyx all contain the mineral calcite while granite and quartzite do not contain it. This means that these two groups of stone must be care for differently. Why is that the case?
Calcite is very sensitive to acids. There are a number of household foods and cleaning chemicals that are acidic. Lemons, vinegar, and even wine are among the liquids that contain acids that dissolve calcite.
Since the stone types that contain calcite cannot be cleaned using acidic cleaners and acidic foods can cause a discoloration known as “etching”, sealing calcareous stones is extremely important. On the on the other hand, granite does not contain calcite and therefore will not etch. However, it is a good idea to seal your granite surfaces to add additional protection.
One last example of how knowing your stone can be helpful. Like granite, quartzite does not contain calcite, so the care and maintenance is similar to that of granite. However, there are stone slabs that get labeled as quartzite that do have calcite in them. Quartzite can look very much like marble. If you are buying quartzite, you will want to be sure that it does not contain calcite. Having a supplier that you trust can be invaluable in this situation.
Just as natural stone can appear similar but be different in composition, so it is with engineered stone. There are a number of engineered stone materials that seem to be alike, but are different. Here is a list of some engineered stone:
- Sintered Stone
These materials are again similar in appearance but very different in composition. Quartz is an engineered stone that is composed of the mineral quartz and polymer resins. It is then formed into slabs and fabricated using methods similar to those of natural stone. On the other hand, the other three materials in that list are engineered without the use of resins at all. Rather, they are produced using a process known as sintering. The raw minerals that are used in the process produce different materials.
Engineered Stone Care
Because quartz surfaces contain resins, it is necessary to protect them from heat and other potentially damaging agents. Quartz can scratch and be burned by hot pans. Additionally, quartz can be cleaned using specific acidic cleaners. Yet, sintered stone can be cleaned using a variety of household chemicals and it is not harmed by high heat. Furthermore, it resists scratching very well and can be used in a number of applications.
Fabrication & Installation
When it comes to stone fabrication the process is pretty standard. There are things that professionals do to cut, shape, and polish the stone that is being fabricated. What changes is how these task are performed.
One example of variations that take place in the way that a part of the fabrication process happens is that different adhesives are used. Each kind of material works best with a particular type of glue and some companies actually offer stone glue to match specific colors of stone. Here is a list of some of the adhesives on CartridgeGlue.com and which stone materials they are designed to work with:
No matter which type of stone material you go with, you want to be aware of not only the available colors, but also what determines what kind of stone it is. Knowing these things will help you when you choose your next stone surface.