Old mud

I'm 3 days into the first orange alabaster piece and have discovered something interesting. Most stones I work with have embedded impurities of one sort or another, but this is the first time I've encountered anything like this. I'm guessing this alabaster was formed about 300 million years ago, so the pocket of mud, most visible in the horizontal photo, is some really old material. It doesn't seem to hold together too well, so the clay content seems to be low. I sure would like to know what went on way back then to produce this effect. Anyway, I'll have to dig that spot out and incorporate it into my design somehow. Very unexpected!
Addendum: I didn't really take the time to think the comments above completely through. If I had,
I would have remembered that alabaster is a metamorphic stone (subject to intense heat and pressure
during its formation) and "mud" would never survive that intact. It seems likely that the material I dug out of the edge is simply some mineral content of undetermined provenance.