The Mine a Planet smelter is the only station in the game that transforms raw ore into the alloys and ingots required for crafting, and every crafting milestone in the game depends on a specific smelter recipe. There are five core recipes that cover the entire progression tree — Common Ingot, Iron Alloy, Titanium Plate, Mythril Bar, and Cosmic Core — plus several Epic-tier alloys that are required for the optional Epic drill crafts. This guide documents every recipe, the exact material ratios, the optimal batch sizes for the 50-stack bulk bonus, and the recommended unlock order so you can plan your smelter pipeline from the first hour to the end-game Void planet.
For a complete walkthrough of how to optimize smelter throughput, including the 50-stack bonus math and parallel queue techniques, see our Mine a Planet smelter optimization guide. For the broader crafting strategy, see our Mine a Planet crafting tier progression guide.
The Five Core Recipes
The five core recipes cover every planet-unlock drill from Wooden Pickaxe through Astral Annihilator. Each recipe has a fixed input ratio, and the smelter applies the 50-stack bulk bonus to any batch of 50 or more. For maximum efficiency, always queue batches that match the recipe ratio exactly.
| Recipe | Input Ratio | Recommended Batch | Output Tier |
|---|---|---|---|
| Common Ingot | 5 Stone + 5 Copper | 50 Stone + 50 Copper | Common |
| Iron Alloy | 10 Iron + 5 Coal | 50 Iron + 25 Coal | Rare |
| Titanium Plate | 20 Titanium + 10 Coal | 100 Titanium + 50 Coal | Rare |
| Mythril Bar | 50 Mythril + 25 Stardust | 100 Mythril + 50 Stardust | Legendary |
| Cosmic Core | 100 Void Shards + 50 Stardust | 100 Void Shards + 50 Stardust | Legendary |
The "Recommended Batch" column is a multiple of the recipe ratio, which means every batch finishes with exactly the materials you need for a clean crafting push with zero leftover ore. Players who queue batches that do not match the recipe ratio end up with stranded ore that they must re-queue, which slows the entire crafting pipeline.
Common Ingot Recipe Detail
The Common Ingot is the foundational recipe and the first one you unlock at the smelter. It requires 5 Stone and 5 Copper per ingot, and the recommended batch size is 50 of each input for the 50-stack bulk bonus. With a fresh Common Ingot, you can craft the Copper Drill (10 Common Ingots) and the Stone Breaker (15 Common Ingots), which together unlock the early-game Earth grinding loop.
| Input | Per Ingot | Per Batch (50/50) | Source Planet |
|---|---|---|---|
| Stone | 5 | 250 | Earth |
| Copper | 5 | 250 | Earth |
The Stone and Copper ore sources are both on Earth, which makes the Common Ingot the easiest recipe to farm. Most players run the Earth 3-node loop described in our fast Drill Piece farming guide to stockpile both ores simultaneously.
Iron Alloy Recipe Detail
The Iron Alloy is the first mid-game recipe and unlocks the Iron Hammer craft. It requires 10 Iron and 5 Coal per alloy, and the recommended batch size is 50 Iron + 25 Coal. The Iron and Coal sources are both on Mars, which makes this recipe the natural follow-up to the Common Ingot once Earth grinding is complete.
| Input | Per Alloy | Per Batch (50/25) | Source Planet |
|---|---|---|---|
| Iron | 10 | 500 | Mars |
| Coal | 5 | 250 | Mars |
With 5 Iron Alloy, you can craft the Iron Hammer, which unlocks Mars for deeper exploration and higher Drill Piece income. The Iron Alloy recipe is also the first recipe where the 50-stack bulk bonus becomes noticeably valuable — the bonus applies to every input, which means a perfect 50/25 batch yields roughly 5-7 bonus alloys on top of the normal 5-alloy output.
Titanium Plate Recipe Detail
The Titanium Plate unlocks the Titanium Spire drill and Europa planet access. It requires 20 Titanium and 10 Coal per plate, and the recommended batch size is 100 Titanium + 50 Coal (which produces 5 Titanium Plates per batch). Because the batch size is 100, you will need the Smelter III upgrade to unlock the 100-stack bonus tier.
| Input | Per Plate | Per Batch (100/50) | Source Planet |
|---|---|---|---|
| Titanium | 20 | 1000 | Mars Deep, Europa |
| Coal | 10 | 500 | Mars |
A complete batch of 5 Titanium Plates is enough to craft either the Titanium Spire drill (3 plates) or the Plasma Drill (5 plates). Most players craft the Titanium Spire first because it unlocks Europa, and they stockpile the extra 2 plates for the Plasma Drill craft later.
Mythril Bar Recipe Detail
The Mythril Bar is the first Legendary-tier recipe and unlocks the Mythril Destroyer drill. It requires 50 Mythril and 25 Stardust per bar, and the recommended batch size is 100 Mythril + 50 Stardust (which produces 2 Mythril Bars per batch). Mythril ore drops only on the Volcano planet, and Stardust drops on Nebula and Void — this means you must clear Volcano first before you can even start the Mythril Bar smelt cycle.
| Input | Per Bar | Per Batch (100/50) | Source Planet |
|---|---|---|---|
| Mythril | 50 | 200 | Volcano |
| Stardust | 25 | 100 | Nebula, Void |
The Mythril Bar is the first recipe where the inputs come from two different planets, which means your smelter pipeline will need to alternate between Volcano and Nebula grinding sessions. Plan your grinding route carefully so that your Mythril and Stardust stockpiles build up at roughly the same rate.
Cosmic Core Recipe Detail
The Cosmic Core is the end-game Legendary recipe and unlocks the Cosmic Reaper and Astral Annihilator drills. It requires 100 Void Shards and 50 Stardust per core, and the recommended batch is exactly 100 Void Shards + 50 Stardust for one Cosmic Core. There is no batch bonus at this tier — every batch produces exactly one Cosmic Core.
| Input | Per Core | Per Batch | Source Planet |
|---|---|---|---|
| Void Shards | 100 | 100 | Nebula, Void |
| Stardust | 50 | 50 | Nebula, Void |
The Cosmic Core is by far the most material-intensive recipe in the game. Crafting the Astral Annihilator requires 3 Cosmic Cores, which means you need 300 Void Shards and 150 Stardust. At realistic grinding rates, this takes roughly 15-25 hours of focused Nebula and Void farming.
Epic-Tier Recipes (Optional)
In addition to the five core recipes, the smelter supports several Epic-tier alloys that are used for the optional Plasma Drill, Quantum Borer, and Solar Flare crafts. Most players skip these because the Legendary drills out-damage the Epic drills, but the Epic recipes are useful for players who want to test the trade market or who are saving Mythril for a later batch.
| Epic Recipe | Input Ratio | Output | Used For |
|---|---|---|---|
| Plasma Alloy | 5 Titanium + 50 Stardust | 1 Plasma Alloy | Plasma Drill |
| Quantum Compound | 2 Mythril + 50 Stardust | 1 Quantum Compound | Quantum Borer |
| Solar Flare Mixture | 3 Mythril + 100 Stardust | 1 Solar Mixture | Solar Flare |
For most players, skipping the Epic crafts and saving the Mythril and Stardust for the Mythril Destroyer and Cosmic Reaper is the optimal progression path. For a complete analysis of when to skip Epic crafts and when to invest in them, see our Mine a Planet crafting tier progression guide.
Recipe Discovery vs Recipe Buying
Some recipes can be discovered through gameplay, while others must be purchased from the in-game shop. Common-tier recipes (Common Ingot, Iron Alloy) are discoverable through basic gameplay. Rare-tier recipes (Titanium Plate, Mythril Bar) require either a rare drop from a specific biome or a shop purchase. Mythic-tier recipes (Cosmic Core) are exclusively shop purchases, with no in-game discovery path.
The general rule is to discover what you can through gameplay, and buy what you cannot. Spending Drill Pieces on recipes that you could discover for free is a waste, while spending Drill Pieces on recipes that have no discovery path is necessary. For the exact recipe discovery locations and shop prices, see our crafting bench smelter upgrade guide which covers the full recipe unlock workflow.
Recipe Ratio Mastery
Every recipe has a fixed input ratio, and mastering these ratios is what separates efficient smelter operators from inefficient ones. The key ratios to memorize are 5 Stone + 5 Copper = 10 Common Ingots, 10 Iron + 5 Coal = 5 Iron Alloys, 20 Titanium + 10 Coal = 5 Titanium Plates, 50 Mythril + 25 Stardust = 2 Mythril Bars, and 100 Void Shards + 50 Stardust = 1 Cosmic Core. Each ratio is designed so that 50-stack queues produce clean batch outputs with no leftover ore.
Players who queue batches that do not match the ratio (e.g., 100 Iron Ore for the Iron Alloy recipe) end up with stranded ore that takes extra queue cycles to clear. The fix is to always queue in multiples of the recipe ratio, which our smelter optimization guide covers in detail.
Frequently Asked Questions
What is the fastest recipe to smelt?
The Common Ingot is the fastest recipe because Stone and Copper both respawn very quickly on Earth, and the smelter completes a 50/50 batch in roughly 2-3 minutes depending on smelter upgrade level. This mechanic is important to master because it compounds with every other progression lever in the game economy.
Should I queue multiple recipes at the same time?
Yes, the smelter supports two parallel queues. The optimal pattern is to queue your main batch on one slot and a smaller byproduct batch on the second slot, which keeps both queues active at all times. Generally yes, but the optimal timing depends on your current resource reserves and your active biome's node HP profile.
Can I store smelted alloys for later use?
Yes, smelted alloys persist in your inventory across sessions and rebirths (assuming they are bound to your account). The smelter does not consume alloys over time. Yes, but the optimal approach depends on your current progression stage and your stockpile of supporting materials.
What happens if I smelt with the wrong ratio?
The smelter will still produce the correct output, but you will have leftover ore in your inventory that does not fit cleanly into the recipe. Always match the recipe ratio to avoid wasted ore. The exact behavior depends on the system in question, but generally the game preserves your cumulative bonuses while resetting current resources.
Do epic recipes have a bulk bonus?
Yes, all smelter recipes benefit from the same 50-stack and 100-stack bulk bonuses regardless of tier. The bonus value scales with recipe complexity, which means Epic recipes see larger absolute bonus payouts than Common recipes. Yes, this works as expected, and the effect compounds with other progression systems, so the value increases over time.
How to Read the Recipe Output for Hidden Bonuses
A subtle detail in the smelter interface is that the displayed output number reflects the base output, not the bulk-bonus output. When you queue a 50/50 Stone/Copper batch, the smelter interface may show "10 Common Ingots" as the expected output, but the actual output after the bonus is 11-12 ingots. The bonus is applied silently when the batch finishes.
This silent bonus is why tracking your actual smelter output across batches is so important. If you see 10 ingots from a 50/50 batch, the bulk bonus is disabled (likely because of a smelter upgrade issue). If you see 11-12 ingots, the bonus is active.
Common Pitfalls When Reading Recipe Ratios
A common pitfall is to misread the recipe ratio and queue a batch that does not produce a clean output. For example, if you queue 60 Iron but only 25 Coal, the smelter will produce 2 Iron Alloys (using 20 Iron + 10 Coal) and then leave 40 Iron Ore stranded in your inventory. Always queue batches that exactly match the recipe ratio.
Another pitfall is to confuse Coal (used for Iron Alloy and Titanium Plate) with Carbon (a different material that does not exist in the current version of the game). Coal is the correct input for the recipes listed above, and using the wrong material name will result in the smelter rejecting the batch.