Here is my first MM Corn Cob Pipe, I bought this back around 1976. I have replaced the stem, many many moons ago.
If you look closely you will see that the cake has penetrated the walls and sealed up those undetectable cracks that are natural to cobs. The cake tends to come through the pairs of dark brown spots that are on the outside of the plaster coated bowl that gives the cob is characteristic corn cob look.
I admit that I had set it down for several years, but with all the discussion about cobs in the forums over the last several months, I put it back into the rotation 5 or 6 months ago. I have gained a new appreciation for the "lowly cob".
My First Missouri Meerschaum Corn Cob Pipe: