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Author Topic: Why does a white cake of soap go dark?  (Read 2485 times)

Offline chris

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Why does a white cake of soap go dark?
« on: 14/08/2011 17:22:54 »
I've noticed that white cakes of soap often darken with age, developing grey patches / lines of discolouration.

My own feeling is that this is where water has penetrated inside the soap, disrupting the crystal structure and therefore making it less reflective, so parts look dark. What do people think?


 

Offline Geezer

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Why does a white cake of soap go dark?
« Reply #1 on: 15/08/2011 07:25:50 »
I always thought those nasty black lines that form in the "crevasses" in the soap were some sort of alien lifeform that had emerged from all the muck on the soap, so I usually throw the bar of soap in the bin when that happens.

 

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Why does a white cake of soap go dark?
« Reply #1 on: 15/08/2011 07:25:50 »

 

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