diff --git a/mods/default/mapgen.lua b/mods/default/mapgen.lua
index 977aac7d..8f020b92 100644
--- a/mods/default/mapgen.lua
+++ b/mods/default/mapgen.lua
@@ -29,7 +29,7 @@ minetest.register_alias("mapgen_desert_stone", "default:desert_stone")
 -- Ore generation
 --
 
-local function generate_ore(name, wherein, minp, maxp, seed, chunks_per_volume, chunk_size, ore_per_chunk, height_min, height_max)
+function default.generate_ore(name, wherein, minp, maxp, seed, chunks_per_volume, chunk_size, ore_per_chunk, height_min, height_max)
 	if maxp.y < height_min or minp.y > height_max then
 		return
 	end
@@ -142,17 +142,17 @@ end
 
 minetest.register_on_generated(function(minp, maxp, seed)
 	-- Generate regular ores
-	generate_ore("default:stone_with_coal", "default:stone", minp, maxp, seed+0, 1/8/8/8,    3, 8, -31000,  64)
-	generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+1, 1/12/12/12, 2, 3,    -15,   2)
-	generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+2, 1/9/9/9,    3, 5,    -63, -16)
-	generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+3, 1/7/7/7,    3, 5, -31000, -64)
+	default.generate_ore("default:stone_with_coal", "default:stone", minp, maxp, seed+0, 1/8/8/8,    3, 8, -31000,  64)
+	default.generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+1, 1/12/12/12, 2, 3,    -15,   2)
+	default.generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+2, 1/9/9/9,    3, 5,    -63, -16)
+	default.generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+3, 1/7/7/7,    3, 5, -31000, -64)
 	
-	generate_ore("default:stone_with_mese", "default:stone", minp, maxp, seed+4, 1/16/16/16, 2, 3,   -127,  -64)
-	generate_ore("default:stone_with_mese", "default:stone", minp, maxp, seed+5, 1/9/9/9,    3, 5, -31000, -128)
-	generate_ore("default:mese",            "default:stone", minp, maxp, seed+8, 1/16/16/16, 2, 3, -31000,-1024)
+	default.generate_ore("default:stone_with_mese", "default:stone", minp, maxp, seed+4, 1/16/16/16, 2, 3,   -127,  -64)
+	default.generate_ore("default:stone_with_mese", "default:stone", minp, maxp, seed+5, 1/9/9/9,    3, 5, -31000, -128)
+	default.generate_ore("default:mese",            "default:stone", minp, maxp, seed+8, 1/16/16/16, 2, 3, -31000,-1024)
 	
-	generate_ore("default:stone_with_coal", "default:stone", minp, maxp, seed+7, 1/24/24/24, 6,27, -31000,  0)
-	generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+6, 1/24/24/24, 6,27, -31000, -64)
+	default.generate_ore("default:stone_with_coal", "default:stone", minp, maxp, seed+7, 1/24/24/24, 6,27, -31000,  0)
+	default.generate_ore("default:stone_with_iron", "default:stone", minp, maxp, seed+6, 1/24/24/24, 6,27, -31000, -64)
 
 	if maxp.y >= 2 and minp.y <= 0 then
 		-- Generate clay