What are these?

pwnell · Post by **pwnell** » Sun Mar 11, 2012 6:17 pm

I was taking photos of newly forming Sodium Sulphate crystals when I discovered that within a couple of minutes all the crystals were being completely covered by these brown spots. Once covered there was no way to see the internal structure of the crystals anymore. They grew very quickly, and it almost seems as if they pop in and out of existence, like bubbles in champagne.
My guess would be that it has something to do with a reaction with oxygen, but I would love to hear a better explanation:

and a 100% crop:

Cactusdave · Post by **Cactusdave** » Mon Mar 12, 2012 12:42 am

This looks like the formation of a different (and less organised?) crystalline phase that quickly becomes dominant.