If you’ve spent hours cruising the alien oceans of 4546B scavenging for rare crafting materials, you know how frustrating it can be to hunt down resources that don’t spawn in common biomes. One of the most sought-after mid-game materials is the compact, high-energy alloy, and finding all mercury 2 locations subnautica players frequent will cut down your grind time drastically. You’ll need Mercury 2 for everything from upgraded Seamoth depth modules to Cyclops shield generators and even late-game Prawn Suit armor, so tracking down consistent spawn points is non-negotiable if you want to progress past the early survival grind. This guide breaks down every reliable spawn spot, what gear you’ll need to collect it safely, and how to avoid the nastiest predators that patrol these areas.
All Mercury 2 Locations in Subnautica: Core Spawn Biomes
Mercury 2 only spawns in mid-to-deep ocean biomes with high geological activity, so you won’t find any in the Safe Shallows, Kelp Forest, or Redgrass Plateaus you explore early on. The three most reliable biomes for consistent Mercury 2 spawns are the Grand Reef, Deep Grand Reef, and Lost River Junction, with a handful of scattered caches in high-elevation underwater caves near Mountain Island too. Mercury 2 outcrops look like dark grey, matte metallic rocks, with a faint purple sheen when you shine a flashlight directly on them, making them easy to distinguish from lighter Titanium or silver outcrops once you know what to look for. Before you head out to any of these locations, make sure you have the following gear to avoid unnecessary deaths or lost progress:
- Seamoth with at least MK2 depth module: Most accessible Mercury 2 spawns sit below 200 meters, so you’ll need this to avoid crush damage before you get the Cyclops.
- High capacity O2 tank: If you plan to exit your vehicle to collect outcrops far from safety, extra air will save you from panic rushes back to the surface.
- Stasis Rifle or Repulsion Cannon: These areas are patrolled by Ghost Leviathans, Crabsquids, and Warpers, so you’ll need a way to defend yourself or escape quickly.
- Laser Cutter: Some of the most consistent Mercury 2 caches are locked inside wrecked storage compartments in these biomes, so you’ll need this to access them.
You can get away with farming the shallowest parts of the Grand Reef with just a MK1 Seamoth and standard O2 tank, but you’ll only be able to collect 2-3 pieces per trip, which won’t be enough for most mid-game upgrades. It’s worth waiting until you have the full gear list above to make your first trip, so you can collect enough Mercury 2 in one go to avoid multiple return trips.
How to Safely Navigate Grand Reef Mercury 2 Spawns
The Grand Reef is the best first stop for new players looking for their first batch of Mercury 2, since it’s easier to access and less dangerous than the Deep Grand Reef or Lost River. You can find the Grand Reef by heading directly south from your starting Safe Shallows escape pod, past the southern Kelp Forest edge, until you start seeing glowing blue table coral formations and tall, spire-like rock structures. Most of the accessible spawns sit between 180 and 300 meters deep, so you won’t have to push your Seamoth to its limit to reach them.
The western edge of the Grand Reef has the highest density of Mercury 2 outcrops, far from the Ghost Leviathan spawns that hang around the eastern border near the Void. If you stick to this western edge, you’ll only run into minor threats like Crabsnakes and Mesmers, which are easy to avoid or stun with your Stasis Rifle. There’s also a small wreck at 280 meters in this western section that holds 8-10 pieces of Mercury 2 in locked storage crates, which is enough to craft your first Cyclops depth module and Seamoth thermal upgrade in one go. I always hit this wreck first on new playthroughs, it cuts out hours of random outcrop farming right when you need the upgrades most.
Just make sure you keep an eye on your scanner while you’re exploring. If you get a Leviathan proximity warning, turn around immediately and head back to shallower water. Ghost Leviathans can one-shot an unupgraded Seamoth if they get a clean hit, so it’s never worth sticking around to grab one more outcrop when you’re carrying a full inventory of resources.
Lost River Mercury 2 Farming Routes for High Volume Hauls
Once you have a Cyclops or a Seamoth with a MK3 depth module, the Lost River is the best spot to farm large amounts of Mercury 2 quickly, especially if you’re building Prawn Suit upgrades or multiple Cyclops modifications. The easiest entrance to the Lost River for new players is the Blood Kelp Trench entrance, located west of the Safe Shallows, past the Grassy Plateaus edge. Follow the winding cave system down until you hit the bright green brine pools, and you’ll be in the Lost River Junction, the central hub of the biome.
The rock walls lining the Junction have 20+ Mercury 2 outcrops spread across a 300 meter stretch, so you can fill your entire inventory in 10 minutes if you move fast. There’s also an abandoned Alterra research base on the northern edge of the Junction that has a cache of 12 Mercury 2 pieces in an unlocked supply locker, no Laser Cutter required. Just watch out for the Crabsquid patrolling the base entrance, it can disable your electronics if you get too close, so stun it with your Stasis Rifle before you go inside.
Warpers patrol the Junction constantly, so keep your weapon out while you’re outside your vehicle. If one teleports next to you, stun it immediately and hightail it back to your Seamoth or Cyclops, they deal heavy damage and will keep chasing you until you leave the area. Also, avoid driving through the bright green brine pools on the Lost River floor, they deal continuous damage to both you and your vehicle, even if you have upgraded armor. Stick to at least 10 meters above the floor to avoid accidental contact.
Common Mistakes to Avoid When Collecting Mercury 2
Even if you know all the spawn spots, it’s easy to make avoidable mistakes that cost you progress or resources when you’re farming Mercury 2. Don’t go hunting for Mercury 2 before you have the MK2 depth module, I’ve lost count of how many times I’ve seen new players try to free dive down to the Grand Reef and run out of air halfway back to the surface, or get their Seamoth crushed when they accidentally dip below 200 meters. Wait until you have the proper gear, it’s not worth the risk.
Another common mistake is mixing up Mercury 2 outcrops with Lead or Silver outcrops when you’re in a hurry. Mercury 2 is significantly darker than both, and has that faint purple glow when light hits it, so take half a second to scan any outcrop you’re unsure of before you waste time mining it. If you’re playing on permadeath mode, bring a spare O2 tank and a spare depth module with you, just in case your Seamoth takes damage or you drop your gear while running from a predator. I learned that lesson the hard way when I lost a 20 hour permadeath save to a Ghost Leviathan attack while I was carrying 15 pieces of Mercury 2 back to base.
Finally, don’t farm Mercury 2 during the early game when you don’t actually need it. It’s easy to get distracted by resource hunting, but you won’t need Mercury 2 until you’re ready to build Cyclops upgrades or Prawn Suit parts, so focus on collecting basic resources like Titanium and Copper first. You’ll save yourself a lot of unnecessary trips to dangerous biomes if you only farm Mercury 2 when you have a specific use for it.
Once you know where to look, collecting Mercury 2 doesn’t have to be the stressful, hour-long grind it feels like when you first start playing. Stick to the western Grand Reef for your first small hauls, then move to the Lost River Junction once you have the gear to handle the deeper, more dangerous biomes, and you’ll never run out of this critical crafting material again. Taking the time to map out all mercury 2 locations subnautica offers will speed up your mid-game progression drastically, letting you focus on exploring the deeper parts of 4546B instead of scavenging for basic resources. Just remember to bring the right gear, keep an eye out for predators, and don’t get greedy if a Leviathan spawns nearby. Happy diving!
