How materials work: everything is data.

Blocks and pieces

Things you carry come in two sizes:

• A block is a whole block of a material. It can be placed in any shape. It counts as 4 units.
• A piece is a quarter block: 1 unit. The game names pieces by what the material is: a wood piece is a Stick, a metal or alloy piece an Ingot, rock and glass pieces are Shards, and a mineral or ore piece is a Chunk. Fibre, seeds, food and the like keep their plain names. A liquid comes as a Barrel.

Crafting counts units, so blocks and pieces mix freely. If a recipe needs fewer units than a block holds, the spare units come back as pieces. A stack holds up to 99. Your bag has an 8-slot belt and a 32-slot grid.

Every block you break drops itself, so any material you can mine you can build with.

Six categories

Category	What it covers	Examples
Element	Pure metals and other elements	Iron, Copper, Gold, Sulfur, Graphite
Mineral	Rocks, ores, gems, soils	Stone, Hematite, Ruby, Clay
Alloy	Metals melted together	Bronze, Steel, Nova Alloy
Compound	Made by reaction or firing, and liquids	Glass, Brick, Gunpowder, Water
Organic	Living and once-living things	Oak, Leather, Wool, Plant Fibre
Exotic	Rare deep, space and legendary stuff	Pyrrhonite, Stellarite, boss trophies

What the properties mean

You can read most of these in the Codex entry of any material.

Property	What it decides
Hardness	How long a block takes to break, and which tool tier is needed. See Tools and tiers. Also its armour and tool value.
Density	Weight. Dense metals make heavy, slow heads, but good radiation shields. Light, flexible materials make dive tanks that hold more air.
Melting point	How hot a furnace must be to smelt it, how hot a furnace made of it can run, and how well a suit shell resists heat. See Smelting and fuel.
Boiling point	Where it becomes a gas.
Thermal conductivity	How fast heat moves through it. A shell that conducts poorly insulates better.
Electrical conductivity	How well it carries power.
Reactivity	How eagerly it reacts. An alloy with enough Chromium becomes stainless.
Flammability and fuel	Whether it burns and how hot and long. Fuel is in MJ per kg.
Toxicity	Poisonous materials such as Lead, Mercury, Cinnabar and Beryllium.
Radioactivity	Uranium, Thorium and some deep materials. See the Radiation Cape in Suits and armour.
Luminosity	Glowing materials give light.
Magnetism	Iron, Cobalt, Neodymium and similar are magnetic.
Elasticity and brittleness	Together they give toughness: how well a tool or suit resists chipping. Brittle materials like flint and obsidian make poor long-lasting heads.
Opacity	How see-through it is.
Nutrition	Food value.
Rarity	How scarce it is. Rarer materials are worth more in trade.

Every material also carries tags such as metal, wood, rock, gem, fibre, fuel and crystal. Recipes use these, which is why many ask for "any wood" or "any metal" and let you choose.

What recipes mean by a group

Recipe says	It accepts
wood	any wood
fibre or hide	plant fibre, cotton, wool, silk, leather, raw hide and similar
stone, clay, brick or metal	any rock, ceramic, building material, clay, metal or alloy
stone or brick	any rock, building material or ceramic
glass or crystal	glass, stained glass or any crystal
metal	any metal or alloy
fuel	any solid that burns
Nova Alloy or stellarite	those two only

Items made or won, such as sprinklers, treasure maps, Guardian's Crests and Gate relics, do not count toward these groups, so you cannot accidentally spend them.

Where the first materials come from

You start with bare hands. Breaking things drops starter parts:

Break	Chance of
Leaves	a Stick of that tree's wood 30%, Plant Fibre 22%
Gravel	a Flint shard 52.5%
Turf	Plant Fibre 20%, Flint 9%, Wild Seeds 14%
Other soil (hardness 0.6 or more)	a Flint shard 10.5%
Cactus	Plant Fibre 30%
Willow wood	Willow Bark 25%

That gives you what you need for a flint tool: see Getting started.

Known and unknown materials

Real-world materials such as Iron and Copper are always identified when you pick them up. The ores and metals of a planet's depths, and all the invented ones, show as Unidentified ore, Unidentified metal, Unidentified crystal, Unidentified organic or Unidentified anomaly. You find out their properties by analysing a sample at a Lab Bench: three stages of 5 seconds each. After that you can give the material a name of your own (up to 32 letters, numbers, spaces, apostrophes and hyphens). See Research and the Lab Bench.

The Codex records a material the first time you hold it. It shows how many known materials you have found and how many invented ones, and how many of those are identified.

Invented materials

Beyond the table of real-style materials, the universe invents more. They are generated deterministically from the planet and the layer, so everyone on a planet finds the same ones. Their names are made up, and their numbers follow the layer: deeper means harder and denser. Some are glowing, some radioactive, some superconducting, and a few are gems. Alloys and compounds you make yourself blend the properties of their ingredients: see Alloys and the Forge.

More about materials

• Metals and their properties
• Rare, deep and exotic materials
• Ores and where to find them

← Back to the wiki · Last updated 25 October 2026. Mantlenaut is in alpha, so things change.