Fields of Mistria Mines Guide: Floors, Biomes & Seals

The Mines are organized into five biome bands. Use this lookup to answer three questions quickly: where am I, what is mainly here, and which seal or quest explains the next gate? It is a lookup aid for the main ore and gem, not a complete list of every monster, forage, fish, or artifact.

Find your biome

• Upper Mines (Floors 1–20): Main ore: Copper Ore. Main gem: Ruby. Next gate: Water Seal.
• Tide Caverns (Floors 21–40): Main ore: Iron Ore. Main gem: Sapphire. Next gate: Earth Seal.
• Deep Earth (Floors 41–60): Main ore: Silver Ore. Main gem: Emerald. Next gate: Fire Seal.
• Lava Caves (Floors 61–80): Main ore: Gold Ore. Main gem: Diamond. Next gate: Ruins Seal.
• Ancient Ruins (Floors 81–100): Main ore: Mistril Ore. Main gem: Pink Diamond. Next gate: Final Seal.

The final floor in a band is a progression checkpoint rather than a normal resource loop. If the next elevator or descent is unavailable, use the named seal in your current objective as the next thing to investigate.

Read the next gate

The five progression gates are Water Seal, Earth Seal, Fire Seal, Ruins Seal, and Final Seal. Steam also lists achievements for breaking each of these seals, which makes them useful milestones for a completion checklist.

When a seal stops your descent:

1. Check the current quest or seal objective outside the Mines.
2. Gather only the materials that objective currently requests.
3. Return to the matching seal floor after the objective is active.
4. Do not spend the day repeatedly farming a biome if the gate is waiting on town, story, or quest progress.

When a seal blocks progress, use the current in-game objective to confirm the required offerings.

Use the resource list

Choose the run by the item you need:

• Copper Ore and Ruby: Upper Mines, for early tool and gem work.
• Iron Ore and Sapphire: Tide Caverns, for the next equipment and crafting tier.
• Silver Ore and Emerald: Deep Earth, when the Fire Seal route is the active progression target.
• Gold Ore and Diamond: Lava Caves, for later crafting and deeper story preparation.
• Mistril Ore and Pink Diamond: Ancient Ruins, for late-game materials and the final Mines route.

These are the main ore/gem targets, not permission to sell every extra find. Keep one copy of unusual resources for Museum, requests, crafting, and progression until those needs are clear.

Prepare for a deeper run

Bring food and leave inventory space for the target ore or gem. A deeper run should have one purpose: progress the current seal, gather a specific material, or build a skill. If the gate is the purpose, check the objective before entering so stamina is not spent on a floor that cannot advance the story.

The 1.0 Mines storyline is complete, including the late progression beyond the early seal sequence. The Ancient Ruins are therefore a late-game navigation and resource section, not a separate unfinished branch.

For the Floor 90 Seed of Balance and Magic Key sequence, use the Floor 90 walkthrough.