A dumped Colnago bicycle&#2c; found at the side of the road

An old Colnago road bike? Dumped at the side of the road? Maybe, maybe not… It was covered in dirt, the tyres were old and cracked and flat, ancient Suntour ten-speed derailleur. Obviously stolen and dumped… but maybe stolen a long time ago! On closer inspection the mystery deepens; firstly, the Colnago stickers don’t look quite right, they’ve faded and aren’t square on the frame, it also seems to weigh a ton. Then I had a look for the serial number — it’s been filed or ground off. The paintwork looks badly applied, and running a thumbnail over it makes it flake off, revealing a metallic red underneath. Just what is it?