Lifting and carrying the 250kg Iron-Nickel Meteorite at the Mt Stromlo Observatory Visitors centre in 2004
I lifted, then carried it around the foyer of the visitors centre and placed it carefully back on its plinth/table
...not being able to just drop it made it extra hard!
Here is the Worlds Strongest Man 2018, Hafthor Bjornsson, doing similar with the legendary 180kg Icelandic Husafel Stone in 2019:
https://www.youtube.com/watch?v=UlRMNwPUdBY