Comparing Marble and Granite
Of the numerous natural stone choices available, two of the long-standing choices are marble and granite. Comparing marble and granite yields interesting results. In this article we will take a look at granite and compare it with marble. We will also look briefly at what the advantages and disadvantages are when it comes to using each of these natural stones.
Natural Marble: An Overview
Marble has long been used in the construction of impressive architecture and notable artwork. For thousands of years this stone has served as the material from which buildings, monuments, and statues have been formed.
Marble is a relatively “soft” material as far as stone goes. On the Mohs scale of mineral hardness (which ranges from 1 to 10), marble comes in at around 3 or 4. Other materials such as granite and quartzite come in much harder (5-7 and 7 relatively speaking).
What Is Marble Made Of?
As a general rule, natural marble is made up primarily of calcium carbonate, also known as “calcite”. It is the calcite content that makes marble soft. However, the calcite is also responsible for other notable properties of marble. Namely, the luster that it is noted for. And if the marble is treated using quality polishing pads for natural stone, even better! We won’t delve into those traits here, but we will in our comparison a bit later. For now though, it is enough to say that marble is predominately made up of calcite.
A Summary of Natural Granite
Like marble, granite has been used in a variety of applications. The list of applications runs pretty much parallel with the marble list. Notable monuments, buildings, statues, and other works are among the many examples of the effectiveness of granite as a building material.
Granite’s Make Up
Granite is usually made up of three main components; feldspar, quartz, and mica. Just like marble, granite gets its properties from its components. One of the main characteristics of granite that contributes to its appeal is its hardness. Granite registers from 5 to 7 on the Mohs scale of mineral hardness – the range in hardness coming from the amount of each component in a given stone.
How Do Marble & Granite Compare?
The comparison between marble and granite can be made in a number of ways. In our discussion though, we will be looking at three basic aspects of these stones. These aspects are:
- Durability – how well does it wear?
- Compatibility – does it work well in multiple designs?
- Sustainability – what is the ease of care and maintenance?
We will compare marble and granite in each of these areas. As we do, we will see how they are similar and how they differ.
Comparing the durability of granite with that of marble involves looking at multiple aspects of wear and tear. The scratch resistance, how easily the material stains, and its response to heat all play a role in making an estimation of a stone’s durability.
Scratch resistance. As mentioned earlier in the post, granite is harder than marble. Its 5 to 7 Mohs rating compared with the 3 to 4 of marble mean it will resist scratching better than its counterpart. In fact, testing a stone’s hardness is actually done by using a “scratch test” whereby the tester uses a sharp object to make a scratch in the stone using pressure.
Design compatibility. Where a particular kind of stone can be used depends not only on its composition, but also on its color variety and visual texture. Granite is available in a variety of color options and patterns. Since each slab of granite is unique, the possibilities are endless.
It is much the same with marble when a comparison is made between it and granite. Marble’s distinct veining is a mark to which many are drawn. At while the “purest” marbles are white, it does come in various colors. As for its compatibility with design styles, marble is compatible with virtually all of them.
Granite Sustainability Compared With Marble’s
Care and maintenance. Sustaining the great appearance of granite takes care and maintenance. And compared with the sustainability of marble, there are similarities.
Similarity: Both Need Sealed
One of the similarities between the two is that both granite and marble need to be sealed periodically. Sealing natural stone helps it to resist staining. Pores of natural stone are receptive to liquid substances. Impregnating sealers make it more difficult for a stone to absorb liquids, thus giving the owner more time to clean up any potentially stain-causing spills before the liquid is absorbed into the stone. The need for sealing also highlights another similarity between marble and granite.
Similarity: Appropriate Everyday Cleaner Needed
Another similarity we see when comparing marble and granite is that each of these materials share a need for using the proper cleaner. Impregnating sealers are broken down by acid. Since natural stone benefits from applying an impregnating sealer, it stands to reason then that only cleaners that are not acidic be used for cleaning them. As a result, pH neutral cleaner is always a good idea for use on natural stones like granite and marble.
Difference: Marble Will Etch
One major difference between marble and granite is that marble will etch when it is exposed to acid. You might be thinking, “what kind of acid?” The answer is any kind! Even tomato juice or acidic drinks and citrus will etch marble very quickly. Sealed or not, marble will etch if any acidic liquid is not cleaned up immediately. Remember, acids breakdown sealer. Just because a stone is sealed does not mean that it won’t etch.
What is Etching?
Etching is a dull spot that is caused by the deterioration of the crystallized calcite in the stone. Earlier we said that the crystals in the calcite are what give the marble its luster. Well, when those crystals are dissolved by acid, it changes the appearance of the stone. But only in the place that the acid contacted it. On polished marble surfaces, the result is a dull spot. On honed marble, the stone looks discolored (usually darker, not as bright).
So an etch is not a stain. Rather, it is an actual deterioration of the stone. There are products made to “remove” etches from marble, but many people simply prefer to not get one in the first place. Preventing etching on marble means cleaning up any spills immediately after they happen. But if one slips by, it is reassuring to know that there are etch removers available.
In the end, marble and granite are 2 very different natural stone materials. Each has its own host of benefits and there are drawbacks as well. However, knowing a bit about how to care for, clean, and maintain whichever of the two you have in front of you will go a long way toward getting the most out of a stone.