{
  "stone_region_system": {
    "resource_type": "construction_materials",
    "description": "Construction stone regions with biome-compatible feature selection",

    "features": {
      "granite_quarry": {
        "display_name": "Granite Quarry",
        "compatible_biomes": ["hills", "rocky_plateau", "alpine"],
        "incompatible_biomes": ["wetlands", "coastal_plain"],
        "pattern": "concentrated",
        "probability": 0.20,
        "quality_base": "premium",
        "extraction_difficulty": "hard",
        "budget_impact": 4,
        "geological_requirements": ["plutonic_igneous_intrusion"]
      },

      "limestone_quarry": {
        "display_name": "Limestone Quarry",
        "compatible_biomes": ["hills", "grassland", "temperate_forest"],
        "incompatible_biomes": ["alpine", "hot_desert"],
        "pattern": "uniform",
        "probability": 0.25,
        "quality_base": "standard",
        "extraction_difficulty": "medium",
        "budget_impact": 3,
        "geological_requirements": ["marine_carbonate_precipitation"]
      },

      "sandstone_quarry": {
        "display_name": "Sandstone Quarry",
        "compatible_biomes": ["grassland", "scrubland", "temperate_forest"],
        "incompatible_biomes": ["alpine", "wetlands"],
        "pattern": "uniform",
        "probability": 0.20,
        "quality_base": "standard",
        "extraction_difficulty": "easy",
        "budget_impact": 2,
        "geological_requirements": ["clastic_sedimentary_formation"]
      },

      "marble_deposit": {
        "display_name": "Marble Deposit",
        "compatible_biomes": ["hills", "rocky_plateau"],
        "incompatible_biomes": ["wetlands", "coastal_plain", "hot_desert"],
        "pattern": "concentrated",
        "probability": 0.10,
        "quality_base": "premium",
        "extraction_difficulty": "hard",
        "budget_impact": 4,
        "geological_requirements": ["limestone_metamorphism"]
      },

      "clay_pit": {
        "display_name": "Clay Pit",
        "compatible_biomes": ["temperate_forest", "grassland", "coastal_plain"],
        "incompatible_biomes": ["alpine", "rocky_plateau", "hot_desert"],
        "pattern": "uniform",
        "probability": 0.15,
        "quality_base": "standard",
        "extraction_difficulty": "very_easy",
        "budget_impact": 1,
        "geological_requirements": ["weathering_accumulation"]
      },

      "sand_deposit": {
        "display_name": "Sand Deposit",
        "compatible_biomes": ["coastal_plain", "grassland", "scrubland"],
        "incompatible_biomes": ["alpine", "rocky_plateau"],
        "pattern": "uniform",
        "probability": 0.08,
        "quality_base": "standard",
        "extraction_difficulty": "very_easy",
        "budget_impact": 1,
        "geological_requirements": ["weathering_erosion_accumulation"]
      },

      "gravel_pit": {
        "display_name": "Gravel Pit",
        "compatible_biomes": ["temperate_forest", "grassland", "hills"],
        "incompatible_biomes": ["hot_desert", "wetlands"],
        "pattern": "clustered",
        "probability": 0.02,
        "quality_base": "standard",
        "extraction_difficulty": "very_easy",
        "budget_impact": 1,
        "geological_requirements": ["fluvial_glacial_accumulation"]
      }
    }
  }
}