Tellurium FAQ

What does Tellurium add?

A small copper-byproduct chain: refinery residue becomes tellurium dioxide, then optical crystals or tellurium metal. Metal makes tellurium copper. Tellurium goes into electric engines, solar panels, accumulators, substations, beacons, laser turrets and the rocket silo. Installing Bismuth adds bismuth telluride and thermoelectric components. With compatible mods, tellurium also improves synthetic rubber yield, supplies optical instruments and goes into power regulators. Factorio 2.1.23 or later in the 2.1 series is required.

Does Tellurium require BZ Lib?

No, as of 0.4.3. Tellurium works without BZ Lib, and existing Tellurium recipes, research and machines are preserved when updating. Keep BZ Lib enabled if another installed mod requires it.

Removing this dependency resolves Tellurium's BZ Lib requirement conflicting with All the Resources Mod (ATRM). Full ATRM compatibility has not been verified; both mods also need to support the same Factorio version.

Does 0.4.0 change an existing Fluffy-only game?

No. Fluffy-only and Fluffy + Space Age keep their existing visible recipes and progression, and do not contain the new precipitate, blank or couple items. The new stages activate with relevant external BZ, Timeken, Planetfall/Ashier, Trikop, K2/K2SO or SE integrations. Each new native material needs a complete, acyclic supply at the existing science tier. New stages do not add productivity multiplication.

For the combined material pack, refining adds neutralisation and furnace calcination; crystals add blank production and polishing; thermoelectrics add nickel/antimony contacts, argon shielding, native advanced cable and polymer housings. Ceramic, solder, cooling and Gallium-interface inputs retain their existing selection rules. Recovery rarity, source coproducts and final consumer doses stay unchanged. Bismuth glass gains chemical-plant access where no BZ multi-input foundry exists.

Existing external lines may need the new feeds and intermediate transfers after upgrading. Old ingredients, completed products, fluids, quality, blueprints and recipe signals are preserved; displaced partial crafts refund their materials. Install the coordinated companion versions listed in the README. The older polished-optics research ID remains available internally so saved research and queue progress survive.

What are the basic refining recipes?

These are the Fluffy-only starter recipes before optional integrations and productivity bonuses. External material packs add the production stages described below. Quantities of acid and water are fluid units.

Tellurium processing unlocks recovery, extraction, reduction and copper alloying. Tellurium optics unlocks crystals. Bismuth adds Tellurium thermoelectrics. These are the two or three branch technologies, depending on whether Bismuth is installed. Space Age adds one infinite Tellurium refining productivity research after optics and Metallurgic science pack: 1.5^L × 1000 red, green, blue, space and metallurgic packs, 60 seconds, for +10% per level. Optional recipes use an existing Tellurium or provider research unlock; their ingredients enforce access to the other production chain. Tellurium does not add new prerequisites to broad upstream polymer, gold or atmosphere technologies. With Molybdenum, advanced oil processing comes after Tellurium processing.

With Space Age, thermoelectric assembly remains available in assemblers and also works in electromagnetic plants. Chemical extraction, chemical reduction and crystal growth also work in cryogenic plants. Copper recovery stays in chemical plants, retaining its furnace-speed balance. The solid alloy also works in foundries.

Where is the tellurium ore?

There is no new ore patch. Select the dedicated copper-recovery recipe in a chemical plant. Ordinary copper smelting remains available and does not produce tellurium residue.

How rare is it?

The baseline recovery recipe consumes 20 copper ore and produces 20 copper plates, plus a 10% chance of one residue. Five residue make one dioxide: an average of 1,000 ore per dioxide before refining productivity. Chance means individual batches can take more or less time. A speed-one chemical plant takes 32 seconds per batch, the same rate as a steel or electric furnace, and averages about 27 minutes for five residue. Plan on a small recovery column rather than one machine: six plants make a dioxide roughly every four and a half minutes.

Why is recovery as slow as a furnace?

Recovery is meant to be a choice. If a chemical plant smelted copper faster than a furnace, every copper line would switch to it and tellurium would stop being rare. At furnace speed, you convert only as many furnaces as your tellurium needs, and the cost is sulfuric acid. Residue per ore stays at 0.5%.

When should I start?

As soon as Tellurium processing is researched. Solar panels need it right away; electric engines for robots, substations and laser turrets arrive with blue science and beacons with production science, and residue builds up slowly. An early recovery column gives you a stockpile when those unlock. The refinery is small, so it is the best place for your first productivity modules: every bonus stretches scarce residue.

Why did coal reduction disappear?

When supported coke, charcoal or graphite production is enabled and reachable in the technology tree, Tellurium uses that processed carbon instead. If multiple processed reductants are supported, each has a recipe. Coal is only the fallback when no supported processed route is active. Upstream settings are respected. Other materials follow the same rule: an enabled, reachable earlier source is preferred over optional enrichment or a late route that would unnecessarily gate the branch.

Which vanilla recipes change?

• Flamethrowers: add two tellurium copper to the handheld and four to the turret for nozzle and valve parts. Existing ingredients and crafting times remain intact. Flamethrower research requires Tellurium processing only where it fits the existing science tier. Already researched saves keep unlocks and gain missing Tellurium research; supply alloy to existing assemblers. Bypass with flamethrower and/or flamethrower-turret. With Magnesium 0.4.5, the handheld also needs two magnesium and one magnesia; turrets keep five magnesia. Antimony 0.3.14 adds one turret bearing lining.
• Accumulator: adds one tellurium copper per item for electrical terminals. In vanilla and the family pack, two iron plates and five batteries still make one accumulator in ten seconds, with the alloy added. Capacity and charging speed are unchanged. Research requires Tellurium processing where it fits the existing science tier without a cycle. Existing researched saves gain missing Tellurium research; saved assemblers need the new alloy feed. Bypass with accumulator. Recycling includes the alloy.
• Rocket launcher: adds two tellurium copper for precision electrical contacts, retaining five iron plates, five gears, five electronic circuits and ten seconds of crafting in vanilla. Rocketry requires Tellurium processing, still at red/green/military science in vanilla and the current family pack. Rocket ammunition and weapon effects are unchanged. Earlier overhaul unlocks are preserved when the alloy would introduce new science packs; bypass with rocket-launcher.
• Electric engine unit: crafted five at a time, with one tellurium copper per batch. Robots, exoskeletons, the rocket silo and utility science all use electric engines.
• Solar panel: crafted ten at a time, with one tellurium metal per batch as the thin-film absorber.
• Substation: +1 tellurium copper.
• Beacon: +2 tellurium copper.
• Laser turret: +1 tellurium-dioxide crystal.
• Rocket silo: +20 crystals.
• Vanilla satellite, where applicable: +4 crystals. Its 100 solar panels also carry tellurium.
• With Bismuth, every tier-3 module (speed, productivity, efficiency and, with Quality, quality) and personal laser defense: +2 thermoelectric components each.

Batched recipes keep every other ingredient and the crafting time per item.

Tellurium optics also grants +10% laser damage and +10% laser shooting speed.

Other ingredients are preserved. Personal laser defense already consumes laser turrets, so no extra direct crystal requirement is added. Power switches, generic circuits and science recipes remain outside the intended consumer set.

What does tellurium-assisted rubber do?

With BrimStuff, the optional synthetic-rubber recipe produces a third more rubber: four instead of three per ordinary batch. It preserves petroleum gas, sulfur, toluene, waste, processing time and machine category. Add one tellurium metal as a reusable charge: each batch returns it with 99% probability, averaging one lost charge per 100 batches. Loop the returned metal back to the input and provide replacement charges. Returned tellurium cannot gain productivity. With Space Age, quality is disabled on this reusable-charge recipe. This is a gameplay abstraction of rubber additives, not an industrial mass balance. It uses the existing polymer research and requires the tellurium material when selected; it does not rewrite the upstream polymer technology. Ordinary rubber, belts and seals stay available without tellurium.

Do I need every listed integration?

No. Bismuth is recommended for the thermoelectric branch, so Factorio offers it during installation; you can deselect it. All other integrations are optional. Choose the mods you want to play.

Which planet mods does it support?

• Corrundum: Refine copper ore to recover a little tellurium residue.
• Paracelsin: Refine copper ore to recover a little tellurium residue.
• Rubia: Build the rocket silo with the planet's own recipe, without tellurium crystals.

What changes with other mods?

The description lists the supported families. Here are the recipe changes for each one; they only apply when a suitable Factorio 2.1 version is installed.

Crushing Industry

Dedicated crushed-copper recovery preserves the effective plate yield. At the inspected defaults, 30 crushed copper, 20 sulfuric acid and 50 water produce 30 copper plates and a 9.5% chance of residue in 48 seconds, matching a speed-2 furnace. The probability accounts for crushing's extra output and returned raw ore. Ordinary crusher recipes gain no tellurium output.

Alloy Smelting and Wood Industry

Tellurium copper and bismuth telluride use existing kiln categories. Coke and charcoal provide processed-carbon reduction and replace the coal fallback. When separate kilns are disabled, Alloy Smelting's converted furnaces provide its solid kiln category. Finished thermoelectric components are assembled rather than smelted.

Lignumis adds no direct peat/lumber reduction; its charcoal connection is through Wood Industry. Tellurium does not gate its starting machines.

pHactorio and chemistry integrations

Existing hydrochloric acid can improve extraction. pHactorio's sodium hydroxide and electrolysis plant enable an alternative reduction route; its plant does not require tellurium to build. Other supported chemistry providers can supply peroxide, hydrogen or argon for additional refining/alloying routes. Peroxide extraction uses three residue per dioxide, versus four for chloride extraction and five for basic extraction: 25% less residue than chloride and 40% less than the basic route, at the cost of five peroxide. Its only fluids are ten sulfuric acid and five hydrogen peroxide; there is no separate water input, so ordinary chemical plants can run it. It unlocks through the existing peroxide production technology. A late alternative does not replace the early core chain.

External refining and thermoelectric assembly

Precipitation and couple assembly below apply when a participating external pack activates the 0.4.0 stages. With pHactorio alone, chloride extraction still makes dioxide directly in 8 seconds.

All precipitation routes finish with 1 precipitate -> 1 dioxide in a furnace, taking 2 seconds. Argon now shields couple assembly; the former six-output argon BiTe shortcut becomes a hidden equal-bill alias to the ordinary dry five-output recipe. Hydrogen and electrolytic reduction offer alternatives to solid carbon. Each route appears only when its materials and required machines are available; the ordinary reachable route remains available when an optional late route is not.

Brevven originals and maintained legacy mods

Graphite supplies a reductant; Foundry supplies alloying machines; Tin supplies solder; Aluminum, Zirconium and Silicon supply candidate ceramics. Chlorine and Noble Metals supply refining connections. Lead, Tungsten and Titanium do not force unrelated new tellurium ingredients. Legacy providers that exclude Space Age remain separate profiles; their compatibility does not imply Space Age support.

Timeken: solder, heatsinks and satellite bodies

Available solder and substrate materials replace the basic copper-cable/stone-brick formulation in the standard thermoelectric recipe. Their production technologies become prerequisites. Tantalite heatsinks or If Nickel cooling fans fit into that same recipe, keep the solder requirement, and raise output from four to six components. There is no equally productive cheap fallback alongside it.

With IntermediatesForYou, the satellite's four-crystal requirement moves into its satellite body. The body technology requires Tellurium optics, and the satellite does not pay the same crystal cost twice.

Planetfall/Ashier: instruments, regulators and rubber

• Lasing Around: scanners and spectroscopes are made in batches of twenty using one optical crystal. All other ingredients and crafting time per instrument stay the same. Shared laser emitters keep their upstream ingredients; laser turrets retain their direct crystal cost.
• Them Thar Hills: adds a tellurium-recovery variant of trace gold from copper, retaining its existing products and taking 25% longer. It also uses one tellurium copper per batch of ten HV power regulators. Other costs and crafting time per regulator stay the same. Equipment that consumes those regulators does not also get a direct alloy charge.
• If Nickel: cooling fans can improve thermoelectric assembly, as described above.
• BrimStuff: adds the optional rubber process described above: a third more rubber, with a 99% chance of returning its tellurium charge each batch.

These integrations preserve existing brass, waste and slag. Bypassed recipes keep their upstream behavior.

Bismuth

Bismuth activates the bismuth-telluride and thermoelectric-component chain. Its glass is preferred for optical crystal growth when it has a suitable production route.

Krastorio 2 and K2 Spaced Out

The existing copper-enrichment recipe gains rare tellurium residue and takes 25% longer, preserving enriched copper, dirty water and other mods’ byproducts. There is no separate Tellurium enrichment recipe; K2's native enrichment processing gate remains in place. Hydrogen and glass can integrate with refinement and thermal assembly. With Bismuth, research servers require four thermoelectric components and quantum computers require eight. Their technologies gain the thermoelectrics prerequisite. The laser artillery turret needs five crystals, one per carbon-dioxide laser, and its research requires Tellurium optics. Advanced solar panels are crafted four at a time with one tellurium metal: the same thin-film charge per megawatt as the vanilla panel, inherited by SE space solar panels. Generic AI cores are unchanged.

Rocket-Silo Construction

The rocket silo is built in stages from an excavation site. The site needs the silo's 20 tellurium-dioxide crystals, once per silo, and its research requires Tellurium optics. Construction stages are unchanged, as are Space Exploration's launch pad and probe silo variants.

Space Exploration

SE delivery cannons can transport residue, dioxide, tellurium metal, tellurium copper, optical crystals and bismuth telluride when that branch is available. They use SE's normal capsule cost and cargo quantities. Finished thermoelectric components use ordinary cargo logistics.

se-pylon-substation gains two tellurium copper. se-energy-transmitter-emitter gains 50 optical crystals and se-energy-beam-defence 20, for beam steering; receivers are unchanged. When the thermal branch is usable, se-space-thermodynamics-laboratory gains four thermoelectric components, se-space-supercomputer-1 20 (higher tiers are built from it) and se-rtg-equipment 10. Their research requires the corresponding Tellurium technology. Upstream ingredients and restrictions remain intact. These changes can be bypassed using those exact recipe names; a cannon entry can be bypassed with se-delivery-cannon-pack- followed by the Tellurium item ID, for example se-delivery-cannon-pack-tellurium-metal.

K2 enrichment already supplies residue before SE molten-copper processing. Lasing Around spectroscopes and laser turrets already carry crystals into SE telescopes and the laser laboratory, so those SE recipes receive no additional direct charge. The SE adapter does not change coolant circulation, science recipes or delivery-cannon capsules.

Space Age

Nauvis recovery remains available. On Vulcanus, foundry melting recipes recover residue while retaining their source outputs and surface restrictions; they take 25% longer. Ore recovery averages 0.005 residue per raw copper ore equivalent, and lava recovery 0.125 per 250 molten copper. A foundry can cast tellurium copper.

On Fulgora, Recycling unlocks scrap recovery: 20 scrap + 10 sulfuric acid + 20 water → 2 copper plates + a 10% chance of residue, in 8 seconds. Electromagnetic plant research unlocks electrowinning: 1 dioxide + 10 electrolyte → 1 metal, in 3 seconds, with the plant's native productivity. No coal or Bismuth is required.

On Gleba, copper bacteria supply the ore for ordinary recovery and biosulfur supplies sulfuric acid. Bioflux processing unlocks bioreduction: 2 dioxide + 1 bioflux + 20 water → 2 metal in 8 seconds in a biochamber (3 metal with its native productivity). Space platform research also unlocks carbon reduction: 1 dioxide + 1 carbon → 1 metal in 4 seconds, in chemical or cryogenic plants. Carbon can come from burnt spoilage or asteroids. These alternatives leave the early coal or processed-reductant routes available.

Advanced asteroid processing unlocks tellurium metallic asteroid crushing: 1 metallic chunk → 10 iron ore + 4 copper ore + a 5% residue chance + the usual 10% returned chunk, in 6.25 seconds. Asteroid productivity improves the ore outputs only; residue and returned chunks are excluded, and quality is disabled. Platforms can make sulfur, water and carbon from asteroids for the refining chain.

Aquilo stays import-based: ship residue, dioxide, metal or finished parts. Cryogenic plants can refine imported inputs, but there is no native tellurium source. Metallurgic-science refining productivity improves extraction, crystal growth and copper alloying, including supported alternatives, without increasing residue recovery.

Fulgora's dedicated recipe consumes 20 scrap, 10 sulfuric acid and 20 water for 2 copper plates and a 10% chance of one residue in 8 seconds. That is about the copper that recycling 20 scrap all the way down would give. It preserves the scrap recipe's surface restrictions. Foundry alloying consumes 1 tellurium metal and 200 molten copper for 20 tellurium copper in 8 seconds. Other planets can import tellurium products. Recycling a beacon, substation, laser turret, solar panel, electric engine or rocket silo returns its tellurium, like the weapons.

Can I add this to an existing save?

No map regeneration is needed because no resources are placed. When the mod configuration changes, recipe unlocks are reconciled with researched technologies; Factorio itself reapplies technology effects. In 0.3.0 this also enables new carbon, electrowinning, bioreduction and asteroid recipes if their provider research is already complete. Existing machine recipes and inputs remain valid. If you have already researched something that now needs tellurium, such as electric engines, solar energy or Rocketry, the missing Tellurium research is completed for you. Its assemblers still wait for tellurium, so build a recovery line soon after adding or updating the mod. The 0.2.2 update keeps existing rocket launchers and assembler recipes; supply two tellurium copper for each new launcher. Back up a save before changing any mod set. Removing content mods can remove their items from a save.

Can I bypass a recipe change?

Use the startup setting for bypassed recipes, with comma-separated internal host recipe names. The modified-recipe diagnostic setting helps identify names. A bypass leaves the named host recipe's ingredients, outputs and unlocks intact; it does not alter unrelated consumer recipes or the other mod's own recipe edits.

Does productivity create infinite tellurium?

Rare residue at the source is excluded from productivity. Material refining can benefit from productivity where supported. Recovery and refining are excluded from automatic reverse recycling so copper, scrap and tellurium cannot be repeatedly converted into additional trace residue. Host recipes retain their own byproducts and exclusions.

How does glass integration work?

The existing crystal recipe uses 1 tellurium dioxide + 20 water + 2 bismuth glass to make 4 crystals in 12 seconds when bismuth glass has a suitable production route. Otherwise it uses 2 ordinary glass when available; without either, the base dioxide-and-water recipe remains. In Fluffy-only games this remains the original crystal recipe. With participating external packs, cast 1 dioxide plus the selected glass into 4 blanks in 8 seconds, then finish 4 blanks with 20 water and one reachable abrasive into 4 crystals in 4 seconds. Gallium pullers support the dry blank stage; the original early chemical plant remains. Its existing optics technology requires the selected glass production technology. Recycling, matter conversion and sources downstream of Tellurium optics do not qualify. The glass represents supporting optical material in the simplified game recipe, not a claim that pure TeO2 crystals are synthesized from ordinary glass.

What do the material-pack integrations add?

Refining adds precipitation and furnace calcination. Crystal production adds optical blanks and polishing. Thermoelectric production adds couples and packaging, with native contacts, wiring, ceramics, gas and cooling supplies where available. The new stages apply only to the participating external material branches.

How should I update a factory that uses material packs?

Back up your save and update the Fluffy material mods you already use together. You do not need to install additional siblings. Existing external production lines may need new ingredient feeds, intermediate transfers or a different crafting machine. Saved materials and recipe references are preserved; check around machines for returned stock after upgrading.

The matching versions are listed in the Caesium FAQ. The companion mods remain optional.

Provider conflicts still apply. BZ + Trikop is supported; Manganese on its own has an upstream steel-furnace limitation that can block progression. Space Exploration and Space Age are separate configurations.