Calacatta Quartzite /cross-cut Bianco Macauba is very hard comparable to Super White / White Fantasy quartzite.

While both materials are considered quartzite they are on opposite ends of the hardness scale. The White Fantasy will perform more like a marble and the Calacatta Quartzite more like a granite.

We have both of these materials in stock.

I have been researching quartzite since I want the heat resistance of granite but like the look of quartzite. I recently read that all quartzite is the same hardness and anything softer is probably marble that was mislabeled?

That is not true and unfortunately there is a lot of misinformation out there about quartzites vs marble. Some quartzites are naturally softer than others and may scratch more easily. When you say you want the heat resistance of granite what exactly are you looking to do? Although granite and other natural stones are resistant to heat they will still be damaged and potentially crack from heat exposure. We have seen it many times where customers have placed a hot pan on their granite countertop and it ended up cracking or at the very least left an ugly mark.