What is the melting point of sandstone?

Answer 1

the melting point of sandstone is approximately 1300.68754893C'

The melting point of sandstone depends on its density, or hardness. Sandstone varies greatly in chemical composition, ranging across different properties, from sand so loosely compacted that it crumbles in the hand, to stone so hard it was once used to mill grain into flour. The higher the density of sandstone, the higher the melting point. Suffice it to say that sandstone, no matter how dense, is never used to make the bricks of a pottery kiln, even though that would be a very inexpensive stone to use, because the stone is not reliable at the high temperatures some kilns sometimes require. For instance, bright white hot, the temperature required to fire stoneware, requires a heat of at least 1300 degrees Celsius, or about 2380 Fahrenheit, for several hours. That much heat would almost certainly, and permanently, damage a kiln made of even the hardest sandstone.

For the same reason, sandstone is no longer acceptable in the building code of most developed nations for the brick of a chimney.