water, dirt,gold, co2 ?
Hmmmmm......?
co2 does seem to carry a lot of weight thees days, especially in the media and gov. ....
and gold has fallen from 2000+ to 1950 so it looks like it must be getting heaver and harder to carry ....
but I think lead gets the prize .... because you have to add in for the brass ....
just saying ..
You don’t know, then. OK.