So usually its made in a kiln around 2,200 and 2,600f, and would then create something beautiful while at the same time being tough, strong, and translucent.
I believe that the metaphors are used to describe the brother and sister. This is because it compares the persons personality to that of a different animal so B.
Hope this helps!
"Orfeo" by Claudio Monteverdi. I might be wrong though :)
