Starting its life as sandstone, quartzite forms when sandstone and quartz are together, under tremendous amounts of heat and pressure. This causes the empty grains of sandstone to become filled with quartz—a process that actually makes the quartzite harder than quartz. Quartzite is a very strong and durable material that possesses a high resistance to heat and stains. Since it’s made primarily of silica, quartzite actually has a very high resistance to anything acidic (which is the culprit of etching). But, in some quartzite slabs, there can be traces of calcium carbonate—a substance that reacts very easily to acid. If these areas come into contact with acids, this can cause localized etching. Etching can range from feeling smooth to rough and may be cloudy looking. You’ll want to contact a stone restoration professional to address these etches.
Keep in mind that quartzite also offers a resistance to absorption and a high hardness rating. Granite has a hardness rating of 6-6.5, Quartzite is around 7, Diamonds are 10. So even if quartzite does come into contact with acidic materials, it will give you more time to clean up before it starts to etch, giving you time to repair it before things get out of hand.
Quartzite is extremely popular not only because of its durability, hardness, resistance to heat, scratches, and water absorption, but also because it looks a lot like marble and has granite-like properties. Many quartzite colors come in shades of light grey and white, which are stylistically very popular today. With just a few protective measures, such as choosing a honed finish over a polished finish or adding a stone sealant for an extra layer of protection, quartzite can be a beautiful countertop that offers style, practicality, and longevity.