Efflorescence is a powdery deposit of salts which forms on the surface of bricks and mortar. It is usually white but efflorescence may be yellow, green or brown. Salts enter the wall from various ...

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Q. Efflorescence is mysterious to many. Does it ever stop forming? My brick three-family is about 120 years old and has an exposed brick wall in the back stairwell. I have lived in the house for 45 ...