Building Materials
When a brick is immersed in water for 24 hours and then dried, if

No grey or white deposits appear on the surface, the brick is free from soluble salts
All listed here
50 percent surface is covered with grey or white deposits, the brick has serious efflorescence
10 percent surface is covered with grey or white deposits, the brick has slight efflorescence

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Building Materials
Putty is

Softened by a solution of pearl ash and quick-lime soaked in water
Used for fixing glass panes
All listed here
Made with finely powdered chalk and linseed oil

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