You can tell a lot by the surface of many things in this world -- people, plants, food...rocks. But you can't tell everything. There have been times I wanted to know more about someone, or a plant, or even the inside of a chocolate iced cake....If I had the desire to know everything (or close to it) about this rock, I would crack it open...but I prefer to just remain mystified this time.
Measures approximately 2 1/4". So says my desk measuring tape.