I think that might be a regional nickname for it - it does indeed form salts which are loosened from the inside of the brick/concrete (both have salts in) by water, and then transported to the outside by the same water.
I can’t find anything relating saltpeter to the term “evanescence” but I know it forms due to humidity + capillarity in stone/brick walls (I recently moved into a house that has some so I only recently started learning about this) so I guess it is the same thing. The scientific name for it is potassium nitrate
Is that how saltpeter forms?
I think that might be a regional nickname for it - it does indeed form salts which are loosened from the inside of the brick/concrete (both have salts in) by water, and then transported to the outside by the same water.
I can’t find anything relating saltpeter to the term “evanescence” but I know it forms due to humidity + capillarity in stone/brick walls (I recently moved into a house that has some so I only recently started learning about this) so I guess it is the same thing. The scientific name for it is potassium nitrate
Efflorescence
Well that explains it