Origins of lamps turn cyan

Why do the origins of lamps turn cyan when one makes additional scenes?

It’s indicating that it’s linked to both scenes. So if you make a change to it while it shares that data block, it will effect both scenes. If you don’t want it to be linked, or if you don’t like the color cyan, just select full copy instead when adding a new scene.

And for some reason this only happens with shared lamps not other objects?

It happens with all objects, as far as I know.

Strange I made the second scene as a copy of the first selecting to link objects

Unlike other objects the lamps had cyan origins and they had them even when not selected.
Other objects were orange.

Did you perhaps create the objects after you duplicated the scene?

nope… but I’ll check again what might be the case.