Material Growing Inside Garage Walls

[tunes7]

Hi, I was hoping someone could help me identify what I've found in my new garage. It's white and looks kind of fluffy and it's on various parts of the wall. The garage was built in the 1940s (I think) and made out of stone.

 

Thanks

[Roundtuit]

Efflorescence?

[Onoff]

6 hours ago, Roundtuit said:

Efflorescence?

 

Bring Me To Life? Great tune.

[tonyshouse]

Sodium nitrate dissolving in water in the masonry and as water evaporates leaves white or clear crystals behind.

 

pinch a small sample, it will dissolve in water

[Roundtuit]

9 hours ago, Onoff said:

Bring Me To Life? Great tune.

Had to Google that.  Every day's a school day!