What quartzite is
Quartzite started out as sandstone. Over millions of years, heat and pressure fused its quartz grains into a dense, hard rock. Polished, it can look like marble, with flowing veins in white, grey, sand and green, but it behaves far more like granite in the kitchen.
Check that it really is quartzite
The trade name on a slab is not always a reliable guide. Some stones sold as quartzite are partly dolomite or marble, and those etch and scratch more easily. Two simple checks help: true quartzite will scratch a glass tile rather than be scratched by it, and a drop of lemon juice left for a minute will not dull it. Ask for both tests on a sample before you commit.
Choosing slabs
Like all natural stone, quartzite varies across a slab. Large islands are where it looks best, so if you want an island top without a join, tell us early. That affects which slabs are suitable and whether one piece can physically get into the house.
Sealing and care
Most quartzite is fairly dense but still benefits from a sealer, particularly lighter colours where oil can show. Wipe it with warm water and a pH-neutral stone cleaner. Hard water troubles it less than marble, though acid descalers will still attack the sealer; a quick wipe round the tap after use avoids the problem.
Silica and quartzite
Because quartzite comes from sandstone, it is very high in crystalline silica. SafeWork NSW puts sandstone at 70% or more. Workshops have to cut it wet, with the same dust controls they use for engineered quartz. Once fitted, it releases no dust in your home.
Questions we are asked
How can I tell real quartzite from soft quartzite?
Ask for a glass scratch test and an acid test on a sample. True quartzite scratches glass and does not dull under lemon juice. Stones that fail either test should be cared for like marble.
Does quartzite need sealing?
Usually, yes, though less often than many granites. At handover you will get the sealing advice for your slab.
Quartzite or quartz?
Quartzite is natural, varied and very hard, but needs sealing. Quartz is consistent and maintenance-free but dislikes heat. See our comparison of all five materials.
Sources
- Natural Stone Institute: caring for natural stone (opens in a new tab)
- SafeWork NSW: crystalline silica in common materials (opens in a new tab)
We are not connected with the organisations linked here; they are listed for reference.