Subnautica Kyanite — Where to Find It and Every Recipe It's In

Kyanite is the last raw material you'll farm in Subnautica, found only in the two Lava Zones at the bottom of the world — the Inactive Lava Zone and the Lava Lakes, roughly 900 to 1,300 meters deep. It appears as angular blue crystals, either loose on the seabed, inside the Lava Castle, or in large drillable deposits. You need it for the final depth modules (Prawn Suit MK2, Cyclops MK3), the Blue Tablet, the Prawn Thermal Reactor, and the Neptune rocket's fuel reserve — so it is the hard gate on finishing the story. This guide covers the routes down, the exact biomes, the drill question, and every recipe that consumes it.

Here's what you'll learn:

• Where the kyanite biomes are and how deep you must dive
• Whether you need the Prawn Suit Drill Arm (and how to get it)
• Every kyanite recipe with exact material counts
• How the Blue Tablet and Orange Tablet fit into the endgame
• The safest route from the Lost River down to the lava

Official resources: Steam store page · Official Subnautica Wiki — Kyanite · IGN Subnautica page · Wikipedia — Subnautica

Per the official Subnautica Wiki: "Kyanite is a blue silicate mineral which forms under high temperature, high pressure conditions. It is resistant to heat up to 1100 degrees Celsius, and is thermoelectric, making it a valuable component of thermal power plants."

Where to Find Kyanite

Kyanite spawns in exactly three places, all in the deep volcanic regions:

The Lava Castle is the mound in the middle of the Inactive Lava Zone's big open chamber, with entrances on its north and south sides. The Lava Lakes sit beneath the ILZ, reached by following the river of flowing lava down through the two access points.

How Deep Do You Have to Go?

Below Zero's deepest area bottoms out around 950 m, but the original game's kyanite lives much lower:

• The Lost River (where you find nickel ore) sits around 800–900 m.
• The Inactive Lava Zone entrances drop from the Lost River through steep descents — the wiki lists two entry points marked by steep drops, reached from the Lost River's Junction.
• The Lava Lakes floor is around 1,300 m, the deepest point of the map.

Practical depth math: a Seamoth caps at 900 m with its MK3 module, so it cannot reach the lava zones at all. You need either a Cyclops with at least a MK1 depth module or a Prawn Suit with MK1 — which is exactly why kyanite gates the MK2/MK3 modules that would make the trip easier. The first visit is always the scariest; bring a full Cyclops with the Prawn docked inside and treat it as the mobile base for the trip.

Do You Need the Prawn Suit Drill Arm?

For deposits, yes — but not for the Lava Castle. The large kyanite deposits can only be mined with the Prawn Suit Drill Arm. However, the Lava Castle contains kyanite in loose crystal form that you can pick up by hand, and the wiki's trivia plus community reports confirm loose crystals also appear on the ILZ seabed. In practice:

• Bring the Prawn Suit + Drill Arm if you want a real stockpile (you'll want 15–20 crystals for all endgame recipes).
• A bare Prawn Suit can grab the Lava Castle crystals without the drill if you're desperate.
• The Inactive Lava Zone is where the Warper density is highest, so stay in the suit.

What Is Kyanite Used For?

Every kyanite recipe, verified against the official wiki and the item pages it links to:

That's the full endgame shopping list: the depth modules get you to the bottom, the Blue Tablet gets you into the final alien facility, the thermal reactor keeps the Prawn alive down there, and the fuel reserve finishes the game. Everything else in the lategame tree branches off these.

The Blue Tablet and Orange Tablet

The two coloured tablets are part of the same endgame progression and worth understanding together:

• Blue Tablet — one sits in the Alien Thermal Plant (inside the Lava Castle). You need it to enter the Primary Containment Facility in the Lava Lakes, and a second crafted tablet unlocks the Moonpool room inside that facility. Recipe: 1 Ion Cube + 2 Kyanite at the Fabricator. Picking it up triggers the Sea Emperor's first telepathic contact.
• Orange Tablet — the rarest tablet, found on a desk in the Deep Grand Reef Degasi Seabase, not in the lava zones. It's used exclusively to open the Lost River Laboratory Cache (where the Sea Emperor eggs are studied and the enzyme research happens). Recipe: 1 Ion Cube + 2 Nickel Ore. You only ever need one terminal unlocked, but the blueprint is worth scanning since the recipe is cheap.

The Safest Route Down

The classic path (cross-checked between the wiki's Lost River page and community route guides):

1. Enter the Lost River through any of its four openings (east of the Mountains/Bulb Zone border, the deep northeastern Grand Reef, the northern Sea Treader's Path, or under the Blood Kelp Islands).
2. Follow the river to the Junction, collecting nickel on the way.
3. Take one of the steep drops at the Junction's far end into the Inactive Lava Zone — you'll pass the Warper and Ghost Leviathan patrols, so keep the Cyclops quiet.
4. Mine the ILZ floor deposits and the Lava Castle, then drop into the Lava Lakes for the Alien Thermal Plant (Blue Tablet) and the Primary Containment Facility entrance.

Bring the Cyclops with the Prawn inside, park it under the Lava Castle's overhangs away from the Sea Dragon's patrol route, and do the kyanite mining in short hops. The Subnautica Cyclops guide has the noise and energy management you'll need for exactly this expedition.

FAQ

Where do I find kyanite in Subnautica?

Only in the Inactive Lava Zone, the Lava Castle and the Lava Lakes — the volcanic biomes between roughly 900 and 1,300 meters deep. Reach them by dropping through the Lost River's Junction.

How deep do I have to go for kyanite?

The first deposits appear around 900–1,000 m in the Inactive Lava Zone, and the deepest (Lava Lakes) sit around 1,200–1,300 m. That's beyond the Seamoth's 900 m limit, so a Cyclops or Prawn Suit with a depth module is required.

Do I need the Prawn Suit drill to mine kyanite?

For the large deposits, yes — only the Prawn Suit Drill Arm mines them. But the Lava Castle and some ILZ floors have loose kyanite crystals you can pick up by hand if you're short on equipment.

What is kyanite used for in Subnautica?

Prawn Suit Depth Module MK2 (3), Cyclops Depth Module MK3 (3), the Blue Tablet (2), the Prawn Suit Thermal Reactor (2) and the Neptune Fuel Reserve (4). It's the final depth and story gate of the game.

Where are the blue and orange tablets?

The Blue Tablet is in the Alien Thermal Plant inside the Lava Castle; the Orange Tablet is on a desk in the Deep Grand Reef Degasi Seabase. Both are craftable after scanning — Blue needs 1 Ion Cube + 2 Kyanite, Orange needs 1 Ion Cube + 2 Nickel Ore.

Related Guides

• Subnautica Prawn Suit Guide — Fragments, Arms and Upgrades
• Subnautica Warper Guide — Where They Spawn and How to Survive
• Subnautica Cyclops Guide — Fragments, Upgrades and Pilot Tips
• Subnautica Gel Sack Guide — Farming Aerogel for the Prawn Suit
• Subnautica Below Zero Map — Biomes, Coordinates & Navigation

Last updated: August 13, 2026.