What You Need to Know About Natural Quartzite Stones

Natural quartzite has become one of the most popular options for high end residential design. Quartzite offers similar aesthetic qualities to marble including vibrant colors and free flowing veins. That said, quartzite is a stronger, more durable stone when compared to marble. This makes it an ideal choice for high traffic areas like kitchen countertops, bathroom vanities, and even fireplace facings. But how do you differentiate between the durability of quartzite and the softness of marble to tell one apart from the other?

Identifying the specific properties of stone isn’t always easy and differentiating stones with similar properties from one another can be another challenge entirely. For example, it is quite common for stones like marble and quartzite to be confused due to their similar appearances, even though they are quite different in terms of their softness/hardness. Fortunately, new diagnostic tests have made it increasingly easier for quarries to correctly identify and differentiate these stones. This ultimately helps reduce the likelihood of misidentification that can then lead to customer complaints down the road.

Differentiating Quartzite from Marble

There are many simple tests that can be done to determine whether the stone you’re looking at has the softer properties of marble, or the harder ones of quartzite.

Hardness Testing

Consider, for example, the glass test. This is perhaps the easiest test available. If you take a piece of glass to a piece of marble, a scratch will be left on the piece of stone. Do the same with quartzite. You’ll notice that no scratch will be left on the surface due to its harder properties. This test can be easily performed with a piece of glass tile from your local tile store and a piece of the stone in question. Keep in mind that you may need to repeat the test a few times to reach a definitive result.

Another option is the knife blade test. Simply get a sample of the stone you’d like to perform the test on and use a spot near the end of the slab in an inconspicuous area. Then attempt to scratch the stone using the sharp blade of a pocket knife. If it leaves a scratch, you are most likely dealing with marble. If not, you’re looking at quartzite.

Acid Resistance Testing

If you’re looking to check for acid resistance in the stone, you can start by experimenting with the lemon test. This involves dripping lemon juice over the unsealed slab of stone and waiting about 15 minutes to assess the results. If you experience any dull spots that seem to be slightly eating away at the surface – also known as etching – you’re likely dealing with some form of marble. Since quartzite is more resistant to acidity than marble, you won’t see much happen to the surface and it should help you easily identify which stone is in question. Just be sure to thoroughly clean up the lemon juice after testing to avoid further etching and damage.

Another option for testing acid resistance in a stone is to create a 10% solution of hydrochloric acid, which you can purchase directly from a chemical supplier. For this test, the nice thing is that you only need to use a single drop of the acid solution on the stone. When the solution comes into contact with marble, it will create small bubbles, but on quartzite, nothing will happen. Keep in mind that in order to observe the results, you may need a magnifying glass or a pair of reading glasses. You’ll also want to be sure to use a sample to complete the test and to only test in an inconspicuous area.

The Bottom Line

Marble and quartzite can look very similar, despite their different properties. As a result, it is important for designers and builders to know how to differentiate these stones when purchasing materials for countertops, fireplace surrounds, and other parts of a home. Otherwise, they run the risk of disappointing their customers if they end up with the wrong stone. Fortunately, these tests can be quickly, easily, and pretty reliably used to make the right call. From there, you can enjoy greater confidence when selecting and purchasing a stone for any given project.

If you’re ready to get started selecting marble or quartzite for your natural stone project, contact Connecticut Stone today to get started, or stop by our showroom in Milford, CT to view materials in person.