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Rare and exotic materials: from the mantle to the stars.
The deep rock, the glowing metals of the core, the stuff of space and the trophies of legends. These are the rarest materials in Mantlenaut.
The rock of each layer
Under the crust, the ground between the ores is a particular rock. It changes with depth (as a share of the planet's depth to the core):
| Layer | Rock | Hardness | Density | Melts at | To dig it |
|---|---|---|---|---|---|
| Upper Mantle | Peridotite | 4.8 | 3.3 | 1400 | Iron (4) |
| Eclogite | 5.2 | 3.5 | 1450 | Iron (4) | |
| Ringwoodite (blue, deep in the layer) | 5.0 | 3.9 | 1600 | Iron (4) | |
| Lower Mantle | Bridgmanite (most common) | 6.2 | 4.1 | 2200 | Steel (5) |
| Ferropericlase (magnetic) | 6.0 | 4.5 | 2400 | Steel (5) | |
| Davemaoite (the rarest) | 6.4 | 4.3 | 2300 | Steel (5) | |
| Outer Core | Taenite (three in four of the layers) | 7.8 | 8.0 | 1450 | Tungsten (6) |
| Kamacite (one in four) | 7.6 | 7.9 | 1480 | Tungsten (6) | |
| Inner Core | Hexaferrum | 9.2 | 13.0 | 5000 | Plasma (7), Coreforged only |
Taenite and Kamacite are metals: melt them together for the Coreforged alloy. Hexaferrum is a metal too, and is among the best materials for a deep-core suit shell. See Alloys and the Forge and Going deep.
Glowing metals of the core
| Material | Hardness | Density | Melts at | Notes |
|---|---|---|---|---|
| Pyrrhonite | 9 | 11.5 | 3900 | Outer Core ore. A glowing, slightly magnetic metal. It is Coreforged by nature: a head of it is tier 8. Unidentified until analysed. |
| Stellarite | 10.5 | 15 | 6500 | Inner Core ore, 2830 to 2990 m. Very bright, mildly radioactive and a very good conductor (80 MS/m). Needs a Coreforged tool. Unidentified until analysed. |
| Nova Alloy | 10.8 | 12 | 7000 | Equal parts Stellarite and Titanium Alloy, forged in Stellarite's own heat. Glows. |
| Heartstone | - | 30 | - | At the very heart of the planet. It cannot be broken. |
As suit shells, Stellarite and Nova Alloy are the best there are. See Suits and armour.
Nova hull plating
At a Lab Bench, 1 Nova Alloy rolled at 3000 degrees makes 4 Nova Hull Plating (hardness 10.5, density 2.4: as tough as the alloy and far lighter). Add a Ceramic for the sand colour or Carbon Fibre for the dark one. These are the hulls of capital ships.
Space
| Material | Notes |
|---|---|
| Voidsalt | Hardness 3.5, density 0.8, glows, unidentified until analysed. A jump fuel of 5000 energy. |
| Helium-3 | A gas of density 0.06, fuel energy 600. A fusion fuel. |
| Regolith | Hardness 1, the dust of airless worlds. |
| Cometary Ice | Hardness 1.2, melts to Water (80% yield). |
| Meteoric Iron | Hardness 5.4, density 6.8. Smelts at 2890 degrees into Star-Iron (50% yield). |
Small rocks in space are made of a mix: metallic ones of Kamacite, Taenite and basalt, with veins of Sperrylite, Chalcopyrite, Ilmenite and Pentlandite; stony ones of basalt, regolith and limestone with Magnetite, Chalcopyrite, Rutile and Graphite; icy ones of Cometary Ice and regolith; and carbon ones of Graphite, Coal and basalt with some Diamond.
Rewards from the far universes
These come only from beyond the Gate: the loot of far universes, their apex creatures, comets and rival ships. They are never found at home. Properties drive the tools and hulls made of them.
| Material | Hardness | Density | Melts at | What it is |
|---|---|---|---|---|
| Star-Iron | 8.2 | 3.2 | 3400 | A hard, light, ferrous alloy. Tool tier 6, with a gun-barrel grade of 2.2. |
| Vitalmetal | 5.2 | 5.5 | 2100 | A living metal. Very elastic and softly glowing. Its plating closes its own wounds between fights. |
| Graviton Crystal | 7.8 | 2.4 | 4800 | A glowing gravity gem. A war hammer with a graviton head is the Gravity Hammer. |
| Voidglass | 9 | 2.2 | 5200 | A dark, phase-shifting glass. A blade of it is a Phase Blade. |
| Runesteel | 7 | 7 | 3100 | Star-Iron, Gold and a Graviton Crystal melted together at 2000 degrees. A gun of it is a Rune gun; a Rune Sword too. |
At a Lab Bench they roll into Star-Iron Hull Plating (1800 degrees, stronger than Nova plating), Vitalmetal Hull Plating (1500 degrees) and the Voidglass Viewport (Voidglass plus Glass at 1800 degrees, 3 made). See Ships and fighters.
The Gate also gives the Home Beacon, which pins the way home on a gate's map, and the Old Gate Relic, which gives a hop for nothing. They are found, not mined.
Trophies
Each legend leaves one trophy when it is slain. A trophy is hard and dense with a gleam of its own, so it also makes a good head for a weapon or tool. The Codex lists all of them. A few examples:
| Trophy | Hardness | Density |
|---|---|---|
| Kraken Beak | 7.5 | 3.4 |
| Mantle Wurm Tooth | 8 | 4 |
| Goldgut Molar | 6.5 | 3.4 |
| Salt King Crown-Shard | 5.5 | 2.4 |
| Gravewell Stone | 8 | 5 |
| Pulse Neutron-Chip | 9 | 8 |
| Gate Warden Sigil | 8 | 4 |
| Azurith Heart | 7.5 | 3.6 |
| Glasswake Lens | 7 | 2.4 |
| Brainless Core | 5 | 1.8 |
Other rewards are the Abyssal Pearl, the Guardian's Crest (hardness 6, a rune crystal dropped once to each player who stood in the fight with the Barrow Guardian), Hive Amber, the Wurm Plate and the Magma Gland (60 fuel energy).
Wurm and sea drops
| Material | Hardness | Notes |
|---|---|---|
| Wurm Plate | 6.5 | Dark armour shell that resists heat (melts at 2600). |
| Magma Gland | 0.5 | Glows. Fuel energy 60, a flame of 2400 degrees: the hottest solid fuel short of the space fuels. |
| Abyssal Pearl | 3.5 | A glowing, very rare pearl. |
| Kraken Ink | 0.1 | A dark pigment and binder. |
| Greyfin Tooth | 5 | A tough bone that can be knapped. A tier 4 tool head. |
Other worlds' own life
Alien planets have their own woods, leaves, turfs and rocks, none of which grow at home. A few of the woods: Coilbark (hardness 2.4), Ribbone (3.2), Cinderstalk (2.8, heat-proof), Glassheart (3.6, translucent), Waxbark (acid-proof), Crystalwood (3.4, glowing) and Hornbone (3). See Ores and where to find them for the elements of other worlds.
← Back to the wiki · Last updated 25 October 2026. Mantlenaut is in alpha, so things change.