Mechanical clocks tell time using gears. They have two important parts: a mainspring and a pendulum. The pendulum keeps time and ensures that the gears move at the right pace: second by second. Instead of a mainspring, some mechanical clocks have weights that pull the gears at the right pace
Yes, hosman, that crossed my mind also but the size is a problem. 7" long and 3 1/2" wide and tin. Put a few of those on a strand and the tree will lean.
It definitely deforms under a hammer blow. After a few blows, it was flat as a pancake (a very small, very thin pancake). Didn't try scratching or melting. The flammability test was to make sure it wasn't some sort of weird grenade - since he was an EOD person, he thinks explosives first.
What I meant about the screw cap was the top part of the screw cap possibly not being original as the workmanship to attach it to the threaded part of the cap is pretty shoddy.
The pineapple juice box is a possibility and it'd be super-healthy with the extra iron. ;D
You might plumb for Wayward's suggestion of it being a pineapple juice carrier, but I think that'll go down like a lead balloon! Grin