In Coalridge area of Langston. Where 60% of The Bone King’s tincture is produced from either ‘volunteers’ or prisoners. This Spark is smuggled out to various cities. The front for the business is that it is where leviathan’s are processed. The area is guarded by some amount of clockwork sentinels. Probably has some wards in place to prevent people from sneaking in.
Rust Alley Whalers sends in Krakens they collect to be processed and get payment via mechanized carts.
After The Bone King fell from power, control of the plant went to The Rust Alley Whalers. Tincture production was halted and prices skyrocketed due to the same level of demand.