As the above write ups note, the d10 is not a platonic solid, which means that when it is spun, it can form two different types of spin.

The first type of spin, and the most likely, is on the jagged middle line, where the obtuse angles meet. If the die is spun on this line, it jiggles from one edge to another, and thus it has more friction and generally spins for a shorter time. When the die is spinning in this fashion, it appears blurry, as it is switching from one edge to another constantly.

a d10 can also be spun on its tip, this is a little bit more difficult to do, but the trick can be learned in probably ten minutes. Since the die is spinning on its tip, it experiences less friction and therefore stays spinning for a longer amount of time. Also, since its shape is not changing, but rotating around a symmetric point, the die almost looks like is standing still.