Grey Mop in dreams
A tool for wet cleaning — the work of dealing with a spill instead of stepping around it.
How grey changes the reading
Grey colour layers ambiguity onto the symbol. The base meaning is still there, but the dream is saying you do not yet have the colour information — the situation has not declared itself.
The base reading of Mop
A mop in a dream is the dream's image of the next step beyond sweeping — the wet work of dealing with what was spilled rather than what was dropped. Mops handle real stains. The dream brings the mop when something has gone wrong recently — a conflict, an embarrassment, an error — and the floor is not going to recover by being walked around. A mop in use is the dream telling you the cleanup is honest and is yours to do. A dirty mop spreading the mess is the dream warning that the method you have been using to clean things up is not actually clearing them — it is moving them around.