Every other lamp/lantern has it right (the other way around.)

actually, if you think about it, the ones that are on should be a bit more luminescent than the off ones. The black one should look a little grayish while on, and darker black when its off.

Hmm.. it looks a bit out of place in the creative inventory, but you are right.
Thanks for the explanation.

When I closely look at gray and ligtgray lamps, the same effect can be seen there.

I guess I'll have to learn not to tell and inverted lamp from a non-inverted one by it being grayish or not.
(Having all non-inverted lamp items grayish and inverted lamp non-in-fog had it's beauty, though.)

What I'm hearing is halos don't render in the inventory. If this is correct
and would solve this issue then I can fix that.

Actually, that would help differentiate the two in the inventory. (That is the problem)