Partial perpetual motion phenomenon

Feb 2020
Nottingham uk
A small metal socket used for hexagonal headed screws/ bolts was inadvertently nudged when lying on my ceramic tiled window cill in my bathroom on March 31 2019
Having my iPhone nearby I decided to record it’s rocking movement as it seemed to be rocking very freely.
After 4 minutes or more I stopped recording in amazement and it came to rest soon after that.
It seems incredible that this object could behave like this for such a long period.
The socket had been taken from my jeans pocket in the early morning before I got dressed. The jeans had not been near any electrical or mechanical devices.
The plain white 15 yr old ceramic tiles on the bathroom window cill do not appear to be the type that would have unusual minerals or metal particles in them.
Can anyone shed some light on this unusual motion.
I have a short extract from the video for those who may be interested.
Nick Borrett
Oct 2017
If the resistance forces are very small, objects can potentially maintain motion for a while. This is true for pendulums; they often maintain their motion for very long durations because the air resistance is very small.

I don't know what forces are being applied (or not) in your system so it's hard to judge exactly what's going on, but I suspect that it's just the case that the ceramic tile is very smooth, so there is is very little resistance.
Jun 2016
The surface of a ceramic tile is essentially glass.
Your socket is probably a stainless chromium alloy.
These two substances have very little attraction to each other chemically,
so there is very little "stickiness" between them.
Assuming that the socket is smoothly and accurately round,
and the tile is smoothly and accurately flat,
there will be very little rolling resistance.

Basically there is very little acting to remove the initial energy imparted by the original nudge,
so it keeps on rocking.
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