I believe dragon tears emit a bright blue light since it is a boss drop. The only drawback is that you can't mount it.
So you firstly need to make sure there is a workbench in range of the place that you want to drop it so that it does not despawn. And then you ideally want to make sure that the place that you drop it is somewhere where you are unlikely to pick it back up.

A self-made lantern frame or some kind of wide pit would help in making their placement look decorative.