its called a crucible and they are specially lined with a hard graphite.

The Bethlehem Steel foundry was a bit similar--thy used an electric furnace to melt down all the scrap steel and took samples to do a chemical analysis before they added it to the molten steel from iron ore and poured the ingots--which were in turn pounded and molded into the shapes they wanted----what a dark dirty environment to work in all day!

I used to work in a foundry. I spent 7 years there as a maintenance technician. Our mold lines were mostly automatic. Sand preparation and supply to the machine was all automatic.
On the main machine the operators had to level the sand out on the mold box before a massive hydraulic cylinder compacted the sand and then another operator put the cores into the mold. The machine assembled both halves of the mold and transferred it to the melt deck where the melt crew poured the molds. We had a 15 ton furnace and a 3 ton furnace when I first started and they were replaced with one 5 ton furnace which could out melt the 15 ton furnace.
We used to take a sample from the furnace and pour a small mold and cool it and test it and that would decide how much additive was needed to bring the metal into spec. The additives were added to the molten metal when it was poured down a launder into a ladle for pouring into the molds. The only thing we used to call a crucible was the little pot on a stick to get a sample from the furnace.
I can't remember the name of the lining for the furnace, launder and ladles but I don't remember it being graphite, I think it was some sort of ceramic. It was loose like powder and was packed around a steel core in the furnace and then the furnace was turned on and the core melted and became part of the next pour. It would last about a month and then it would have to be replaced. It came out like concrete. The top foot or so was chipped out by hand and then the furnace was tilted and a big hydraulic cylinder was attached to the base and the rest was pushed out.
Charging the furnace was the dangerous part as the scrap had to be dry and free of aluminum cans or anything that could hold moisture. We had a big explosion there one day when a charge that was dropped into the furnace contained trapped moisture. Water instantly turns to steam when dropped into molten metal and can cause a molten metal shower to explode from the furnace. Luckily on our explosion no one was hurt.

i worked in a engineering shop that used to cast there own slasher gearbox housings. what they had for a melt pot was called a crucible as it was small would have only held about 30 litres of water and it was a special graphite ceramic material can't remember exactly what it was called they had stopped casting yrs before as you could buy em cheaper made in Taiwan and it was the last one they had. the bloke who owned the place was in his mid to late 80s his dad died aged 105 when i worked there. and old george was a bit of a pack rat half used 680 weld-all electrode with half the flux missing no dont throw that out its a good bit of steel never use it but cant throw it away. i swear the first bit of grease and oil spilled on the floor was still there 50yrs later.

the qld premier in the 80s was sir Joh, now Joh was staunch anti trade union he believed this shop needed a trade union. 2 youngish blokes were killed there 70s/80s when a cylinder of acetylene made from calcium carbide exploded old george still had the gas producer over 20yrs later and a couple of 44gal drums full of calcium carbide chunks.

george was a cantankerous old barstard but what he didn't know about about making non electronic farm machinery and blacksmithing possibly wasnt worth knowing.

Watch the next u-tube video about rebuilding a starter armature. Never imagined that and I worked in a starter rebuilding shop for 3 years.