Why can't I find Furnace III?
Because it does not exist.
After Bronze and Iron, the obvious assumption is:
Furnace I → Bronze
Furnace II → Iron
Furnace III → Steel
Graveyard Keeper 2 deliberately breaks that pattern.
Steel Ingot is not part of the Keeper's normal smelting chain. It comes from the Royal Foundry, while you use purchased ingots to craft 
Steel Details, 
Steel Screws, tools, armor and other late-game items.
So if you have:
Iron technologies;
late steel-looking technology nodes;
but no Steel Ore or Steel Ingot recipe;
you have not missed a furnace upgrade.
You need story progression and 
Jack reputation.
When does Steel unlock?
Steel is a fairly late progression tier.
The key character is Jack.
His reputation gates most of the industrial branch:
60 → the next industrial story step;
80 → further Factory progression.
Steel is therefore not simply a matter of farming enough red tech points.
You first need to advance Jack's quest line.
How to reach 60 reputation with Jack
If you are already working with the Factory, much of this path is behind you.
Jack reputation rises through his own ordered quest chain, including:
- 1
the early Jack in a Boat sequence;
- 2
restoring his workshop in Town;
- 3
- 4
the post-election industrialisation storyline.
At 60 reputation, Jack starts discussing the larger industrial problem and the lack of steel matching the quality of the old Royal Foundry.
That is where the game finally points you toward Steel.
If the Factory itself is still confusing, see Factory Automation and Conveyors.
Where is the Royal Foundry?
The Royal Foundry is beneath the old bathhouse in the northern Town area.
You cannot simply walk in at the beginning of the game.
Access comes through later Town/combat progression involving the flooded water route and the battle that opens the bathhouse basement.
Inside you meet the monks and their leader, Brother Bishop.
This is the game's normal source of Steel Ingots.
How to buy Steel Ingots
During Man of Steel, ask Brother Bishop about the steel made in the Foundry.
Important: this is not a normal Trade screen.
Steel is purchased through a dialogue choice.
You can buy batches of:
The price never changes:
1 Steel Ingot = 1 silver
There is no bulk discount.
Ten ingots cost 10 silver and 100 cost 100 silver.
If you open the Bishop's ordinary trading interface looking for steel, you will not find it there.
What do you do with the first three Ingots?
Man of Steel asks you to prove the quality of the material.
Buy 3 Steel Ingots and bring them to Jack.
Completing the hand-in:
gives +10 Jack reputation;
takes him to 70;
From there, Steel becomes a real crafting tier.
I have 70 reputation. Why is Steel Smithing still locked?
Reputation technologies in GK2 may only visibly update when you reopen the technology tree.
Close and reopen it.
The reputation gate itself costs no ordinary tech points. It simply exposes the next technology.
Then purchase Steel Smithing normally.
Current cost:
120 red tech points;
15 blue tech points.
What does Steel Smithing unlock?
The core technology opens:
The Steel Anvil is built in your yard and costs 4 Steel Ingots.
That means the three ingots used for Jack are not enough to start actual steel production.
After completing the quest, return to the Bishop and buy more.
How to make Steel Detail
At the 
Steel Anvil:
1 Steel Ingot
→ 4 Steel Detail
Requirement:
Smithing Mastery 10
This is one of the first major Mastery checks of the steel tier.
If the technology is open and the anvil exists but the recipe is grey, the problem is likely your Mastery rather than story progress.
See Mastery Explained and Jewelry Table and Mastery Equipment.
How to make Steel Screws
Steel Screws are also produced at the Steel Anvil from a Steel Ingot.
Base recipe:
1 Steel Ingot
→ 8 Steel Screws
They require Smithing Mastery 11 — one point higher than Steel Detail.
Screws quickly appear in:
late construction;
advanced devices;
Town upgrades;
story machinery.
Do not convert every early ingot into tools without checking the next few builds.
Steel tools
The steel branch eventually opens the third tier of normal tools.
For example:
Steel Axe
Steel Pickaxe
Uses the same core metal cost and also needs Smithing Mastery 10.
Steel Hammer
Again uses Steel Details + Ingot and the Hardening Bucket.
Steel tools are not merely speed upgrades. Their Mastery bonuses help meet late recipe requirements across multiple systems.
Steel Sword and Armor
Steel also feeds combat progression.
The 
Steel Sword needs multiple Steel Details and Ingots with high Smithing Mastery.
Steel Armor is even more expensive in raw metal.
Do not buy only four ingots for the Steel Anvil and expect the entire tier to be solved.
If you are actively progressing battles, keep a larger steel budget.
See Combat and Zombie Squads.
Can you mine Steel Ore?
No.
The current player-facing production data has no normal Steel Ore → Steel Ingot chain.
Zombie Miner does not produce Steel either.
It produces 
Iron Ore and 
Coal.
Even a fully automated mine therefore does not remove your dependence on the Bishop for raw Steel Ingots.
See How to Unlock Zombie Gathering.
Can you buy Steel somewhere else?
Developed Town vendors can later sell some steel-related products such as Steel Details, Screws and finished equipment.
But raw Steel Ingots are tied to the Royal Foundry/Bishop route.
If a recipe specifically needs an Ingot, the Bishop is the reliable source.
How much Steel should you buy?
For the first transition, budget for at least:
Seven ingots only covers the quest and workstation, with almost no production buffer.
If your economy is already healthy, buying 10–20 at once is convenient.
It is not cheaper per ingot, only fewer trips.
Why is Steel so expensive?
Because late Steel is deliberately separated from your automated smelting economy.
By the time it opens, the game expects you to have stronger money systems:
Town trade;
sermons;
supply orders;
Factory production;
zombies.
If one silver per ingot still feels impossible, your economy may be the real blocker.
See How to Make Money.
FAQ
Where is Furnace III?
There is no Furnace III for player Steel production.
Where do I buy Steel Ingots?
From Brother Bishop in the Royal Foundry beneath the bathhouse.
Because it is sold through a dialogue option.
How much does one Steel Ingot cost?
1 silver, regardless of batch size.
How do I unlock Steel Smithing?
Reach 70 reputation with Jack through Man of Steel, then purchase Steel Smithing with tech points.
What should I make first?
Build the Steel Anvil first, then convert ingots into the Details/Screws needed for your immediate blockers. Upgrade tools when their Mastery bonus becomes valuable.
