The "half" icon is not much different from the original one. One with more variance would definitely do. I don't want to make it rely on the black background behind the bar, as shown in the screenshot, it can be easily hidden by darkness.ah, ok then. Would teh second work for that? Or would you prefer something else?
EDIT: Actually, I believe a "smaller" drop could also work pretty well, as long as it is centered inside a 14x18 sprite.