My favorite crucible is the Burno which comes in three pieces.
Melting dish, the hood which covers the dish, and tongs. I use iron
bindingwire to securely fasten the tongs to the crucible. That way
it cannot come apart at an inopportune moment. The reason I like it
is that it holds the heat well, when melting my silver, and best of
all has a lip, so that pouring the molten metal is very easy, and
the silver goes where it is intended. Rio Grande has them.
I gave a workshop in cuttlebone casting, and the funnel we cut into
the cuttlebone is quite small, and takes accuracy in pouring. Those
using the Burno had complete success, even though it was their first
time melting and pouring metal.
Another crucible is the “Whip” also carried by Rio. I have not used
it, but it has been highly recommended by several Orchidians in the
past. Whichever you get, be sure to season it well with theborax
flux—good old 20 Mule team works just fine. You will get
directions with the crucible, or on the Rio website. Alma