Chimney breast pad stone

[a9blue]

I plan to remove a chimney breast from a bedroom. The breast above it in the loft has what looks like a 4 inch grey slab just above the loft floor level.
Is this a pad stone and does it mean that it will support the chimney stack above it so that I can remove the breast below it?

 

[tony1851]

Probably not, but a pic or two would certainly help here.