FIND // PDA CASE FILE
Can't Find Crystalline Sulfur in Subnautica
Crystalline Sulfur is not the same resource as early Cave Sulfur. It appears in the Lost River and lava regions, usually behind the deep progression route and its green-brine hazards.
LAST CHECK
ANSWER LOCK // QUICK RESPONSE
Search the Lost River under the green brine, then the Inactive Lava Zone, Lava Castle, and Lava Lakes. Do not search shallow caves for Crystalline Sulfur; that is where Cave Sulfur belongs.
SIGNAL CONFIRMEDLOCATION SCAN
BIOMELost River, Inactive Lava Zone, Lava Castle, and Lava Lakes
DEPTHDeep-game route, including areas below the Lost River
REQUIRED EQUIPMENTVehicle with appropriate depth module, Prawn Suit or another safe brine-collection plan, Repair and power backup
BRING THIS
- Vehicle with appropriate depth module
- Prawn Suit or another safe brine-collection plan
- Repair and power backup
DATA ACCESS LEVEL
Reveal only as much as you need
02 // DIRECTIONDirectionROUTE GUIDANCE
03 // EXACT ANSWERExact answerFULL SPOILER
COMMON REASONS YOU ARE STUCK
- Searching the Safe Shallows or Kelp Forest
- Confusing Crystalline Sulfur with Cave Sulfur
- Entering green brine without a safe collection plan
- Stopping at the Lost River when the needed supply is in the lava zones
EVIDENCE LOG
Verification record
Facts on this page are separated from player speculation. Version-sensitive answers should be rechecked after an official update.
LAST CHECK2026-09-01
- SOURCE // 01Crystalline Sulfur OPEN SOURCE ↗WIKI · checked 2026-09-01
- SOURCE // 02Lost River OPEN SOURCE ↗WIKI · checked 2026-09-01
- SOURCE // 03Inactive Lava Zone OPEN SOURCE ↗WIKI · checked 2026-09-01