I think It's the copper kettle used in the cauldron.
No
what are the children walking next to the flag bearer carring in the Olympic parade of nations
The country which appears first in the Olympic Parade of Nations is always Greece, because Greece started the Olympic Games thousands of years ago. And the last country to parade is the host country.
The ashes of Olympians past?
Parts of the Olympic torch.
Each nation has one flag bearer and another Olympic escort carrying a copper leaf. The leaves were later lit with the Olympic torch and then combined to create the cauldron
They become part of the Olympic beacon at the end of the parade.
Zimbabwe
Torch bowl
Funnel
Funnel
In the 2012 Parade of Nations, the girls leading each country's athletes were carrying the petal of a giant flower. Its purpose becomes evident at the end. When the games are finished, the flower will be dismantled and each country gets to take a petal home.