Overview
A blast furnace smelts ores and metal items at exactly twice the speed of an ordinary furnace — 5 seconds per item instead of 10 — in exchange for two restrictions. It only accepts ores, raw metals and metal tools and armour, so it will not smelt food, sand, clay or logs, and it grants half the experience a normal furnace would for the same job. For a player processing a mining trip's worth of raw iron and gold, that trade is obviously worth taking; for a player farming experience through smelting, it is not. The other reason to build one is villager trading: the blast furnace is the Armorer's job site block, and an Armorer is one of the most useful villagers in the game, selling enchanted diamond armour and buying coal for emeralds. Placing one beside an unemployed villager assigns that profession, and breaking and replacing it rerolls their trades until they have the enchantment you want. Mechanically it behaves like a furnace in every other way: same three slots, same hopper interactions, same comparator reading, and it emits light when lit.
Processing a whole mining trip's worth of ore and raw metal at double the speed of a furnace, and serving as the Armorer villager's job site block, which unlocks enchanted diamond armour trades and coal-for-emerald deals.
Blast Furnace is a functional block in Minecraft Java Edition 1.21.4. Blast Furnace has a crafting recipe, so it is renewable as long as you can source its ingredients. At hardness 3.5 this is one of the tougher blocks in the game.
It needs at least a wooden pickaxe to drop anything; a weaker tool destroys it for nothing. Mining it returns the block itself, so it is safe to relocate. A full stack holds 64.
It is crafted from Iron Ingot, Furnace, and Smooth Stone. Nothing on the crafting grid is made from it.
How to get it
Craft it from 5 iron ingots, 1 furnace and 3 smooth stone. Smooth stone is stone smelted a second time, so budget 3 extra smelts on top of the cobblestone for the furnace itself.
Tips
- It smelts at 5 seconds an item against a furnace's 10, but gives only half the experience per smelt.
- It refuses food, sand, clay and logs entirely — keep an ordinary furnace or a smoker alongside it.
- Break and replace the block beside an unemployed Armorer to reroll trades until Protection IV appears.
- Run 2 blast furnaces off 1 hopper line for a mining haul; the bottleneck is usually fuel, not speed.
How long it takes to break
Hardness 3.5 puts Blast Furnace at 18 seconds a block bare-handed, or 0.6 seconds with the right tool at netherite tier.
Iron takes 0.9 seconds against diamond's 0.7, so the upgrade worth making for this block is the one to iron.
The block still breaks with a weaker tool, but below wooden it yields nothing at all — the time is spent and the drop is lost, which is the single most common way players waste a vein.
Each Efficiency level adds level² + 1 to the tool's speed, so a level V tool clears this about 4 times faster than an unenchanted one.
| Tool | No enchantment | Efficiency III | Efficiency V |
|---|---|---|---|
| Hand * | 18 s | 18 s | 18 s |
| Wooden | 2.7 s | 0.45 s | 0.2 s |
| Stone | 1.4 s | 0.4 s | 0.2 s |
| Iron | 0.9 s | 0.35 s | 0.2 s |
| Diamond | 0.7 s | 0.3 s | 0.2 s |
| Netherite | 0.6 s | 0.3 s | 0.15 s |
| Golden | 0.45 s | 0.25 s | 0.15 s |
Properties
With 3.5 blast resistance Blast Furnace usually goes down to a nearby explosion. It is fully opaque and produces no light. One inventory slot holds 64, the normal full stack. The block is tagged for pickaxes, and only that class gets the speed bonus; everything else mines at bare-hand rate.
- Transparent
- No
- Required tool
- Wooden Pickaxe
Crafting recipe
Crafting Table
Blast Furnace
Drops
Mined with Wooden Pickaxe, Blast Furnace drops itself.
Guides and tools that cover this
Frequently asked questions
How do you get Blast Furnace in Minecraft?
Blast Furnace is crafted from Iron Ingot, Furnace, and Smooth Stone.
What tool do you need to break Blast Furnace?
Wooden Pickaxe or better is required; anything weaker destroys the block without dropping it.
Is Blast Furnace blast resistant?
Blast Furnace has a blast resistance of 3.5, so an explosion nearby will destroy it.
How many Blast Furnace fit in one stack?
Blast Furnace stacks to 64, which puts 3,456 of them in a double chest.
How long does Blast Furnace take to break?
0.6 seconds with a netherite-tier tool of the right class, or 18 seconds bare-handed.
