Another question is about the carbon crucible, I notice it has a very high melting point which would be useful for me but I can’t figure out if it is just a placeholder for now or if its actually craftable the the NEI isn’t showing me a recipe.
Ah right I forgot about the “Graphite” Crucible, I really need to look up how those are made IRL. Though I would put them as high tier thing, so you cant get them early on.
It would appear at first glance they can be constructed by extrusion of graphite clay, a mixture of graphite, silicon carbide, aluminosilicate and silicon dioxide but these only reach up to about 1922K.
Real carbon crucibles using glassy ‘vitreous’ carbon, can withstand up to 3273K and are corrosion resistant so would be able to withstand acids.
I can’t find much on how they are constructed other than their discovery which happened when sellotape holding ceramic material kept a structural identity after firing in an inert atmosphere.
This technique was used to make crucibles from diamond structured resole resin that could be shaped in a crucible form.
EDIT: a link to a patent on the glassy carbon production process:
Glassy Carbon and process for production thereof
Seems the resole resin is formed into a crucible, heat cured and then fired in a non-oxidizing environment. Noting that heat curing produces a lot of water.
As for the high heat the current carbon crucible can withstand, another form of carbon was discovered in 2011 that was formed from material under high pressure, referred to as diamond-like carbon. but its more similar to amorphous carbon, that is carbon without a crystalline structure, just really crushed together.