Seal -- The Wedding Ring Is Finally OFF

Seal has finally surrendered to the reality that his wife is leaving him -- 'cause for the first time since the split, the singer was spotted without his wedding ring.

Right after the split, Seal appeared on "Ellen" and said he had "no intention" of removing the wedding band because "It's a token of how I feel about this woman" ... adding, "It feels really comfortable on my hand."

But the singer clearly wanted to send a message when he arrived in Australia this morning -- 'cause dude had bright yellow nail polish on his fingers, which drew even more attention to the fact he was sans ring.