The post is attached to one side of the bezel that holds the "simulated Diamond," rather than on center. Perhaps this is to allow more light to shine through from the back, since the back is "open." See attached photo.

I got one of them wet to see if it would change its appearance permanently from the "un wet" one. When it was dry, there was very little difference in appearance between the two. I had to look hard to see that the one that had gotten wet didn't have quite as much luster, but I would expect that of any piece of jewelry that might get wet and then dry with a little water residue left on it.

They are pretty, and seem to stay that way. I haven't put them in any 'cleaning" solution yet to see how they fare. That will have to wait for the next time.