In my photo here, the light color indicates crystallization or honey that is or has turned solid, while the dark color indicates liquid honey. By holding a jar up to the light, you can sometimes see the crystals floating in suspension. I always think about ancient Egyptians when I see hardened honey, because people have found it in tombs, and it never went bad. It just got hard. Three thousand years ago. I think that is a very cool attribute for food to naturally have.
You can soften and liquefy your honey easily with some hot water and some time. I place a deep saucepan of water on my stove, bring it to steaming, turn off the heat, and put my jar of honey into the water bath — but keep the water line below the lid. After that, it’s a matter of time before my honey melts. For small jars, I can have the lower 25% of the jar in the hot water bath and the entire contents will end up liquefying. I have a photo of it on my Examiner page.