diff --git a/src/main/java/com/hbm/world/feature/OreLayer3D.java b/src/main/java/com/hbm/world/feature/OreLayer3D.java
index 4f330c4a0..30be4d4c9 100644
--- a/src/main/java/com/hbm/world/feature/OreLayer3D.java
+++ b/src/main/java/com/hbm/world/feature/OreLayer3D.java
@@ -1,33 +1,43 @@
 package com.hbm.world.feature;
 
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
 import java.util.Random;
+import java.util.Set;
 
 import cpw.mods.fml.common.eventhandler.SubscribeEvent;
 import net.minecraft.block.Block;
-import net.minecraft.block.material.Material;
 import net.minecraft.init.Blocks;
+import net.minecraft.world.ChunkCoordIntPair;
 import net.minecraft.world.World;
 import net.minecraft.world.gen.NoiseGeneratorPerlin;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.event.terraingen.DecorateBiomeEvent;
+import net.minecraftforge.event.world.WorldEvent;
 
 public class OreLayer3D {
-	
+
 	public static int counter = 0;
 	public int id;
 
+	long lastSeed;
 	NoiseGeneratorPerlin noiseX;
 	NoiseGeneratorPerlin noiseY;
 	NoiseGeneratorPerlin noiseZ;
-	
+	double[][] cacheX;
+	double[][] cacheZ;
+
 	double scaleH;
 	double scaleV;
 	double threshold;
-	
+
 	Block block;
 	int meta;
 	int dim = 0;
-	
+
+	Map<Integer, Set<ChunkCoordIntPair>> alreadyDecorated = new HashMap<>();
+
 	public OreLayer3D(Block block, int meta) {
 		this.block = block;
 		this.meta = meta;
@@ -35,22 +45,22 @@ public class OreLayer3D {
 		this.id = counter;
 		counter++;
 	}
-	
+
 	public OreLayer3D setDimension(int dim) {
 		this.dim = dim;
 		return this;
 	}
-	
+
 	public OreLayer3D setScaleH(double scale) {
 		this.scaleH = scale;
 		return this;
 	}
-	
+
 	public OreLayer3D setScaleV(double scale) {
 		this.scaleV = scale;
 		return this;
 	}
-	
+
 	public OreLayer3D setThreshold(double threshold) {
 		this.threshold = threshold;
 		return this;
@@ -58,29 +68,52 @@ public class OreLayer3D {
 
 	@SubscribeEvent
 	public void onDecorate(DecorateBiomeEvent.Pre event) {
-
 		World world = event.world;
-		
+		int cx = event.chunkX;
+		int cz = event.chunkZ;
+
 		if(world.provider == null || world.provider.dimensionId != this.dim) return;
 
-		if(this.noiseX == null) this.noiseX = new NoiseGeneratorPerlin(new Random(event.world.getSeed() + 101 + id), 4);
-		if(this.noiseY == null) this.noiseY = new NoiseGeneratorPerlin(new Random(event.world.getSeed() + 102 + id), 4);
-		if(this.noiseZ == null) this.noiseZ = new NoiseGeneratorPerlin(new Random(event.world.getSeed() + 103 + id), 4);
-		
-		int cX = event.chunkX;
-		int cZ = event.chunkZ;
-		
-		for(int x = cX + 8; x < cX + 24; x++) {
-			for(int z = cZ + 8; z < cZ + 24; z++) {
+		ChunkCoordIntPair chunkPos = new ChunkCoordIntPair(cx, cz);
+		Set<ChunkCoordIntPair> decoratedChunks = alreadyDecorated.computeIfAbsent(world.provider.dimensionId, n -> new HashSet<>());
+
+		// Stop early if we've already generated this chunk in this dimension
+		if(decoratedChunks.contains(chunkPos)) return;
+		decoratedChunks.add(chunkPos);
+
+		// refresh caches on first run and if the world seed changes
+		if(this.noiseX == null || world.getSeed() != lastSeed) {
+			this.noiseX = new NoiseGeneratorPerlin(new Random(world.getSeed() + 101 + id), 4);
+			this.noiseY = new NoiseGeneratorPerlin(new Random(world.getSeed() + 102 + id), 4);
+			this.noiseZ = new NoiseGeneratorPerlin(new Random(world.getSeed() + 103 + id), 4);
+			cacheX = new double[16][65];
+			cacheZ = new double[16][65];
+			lastSeed = world.getSeed();
+		}
+
+		for(int o = 0; o < 16; o++) {
+			for(int y = 64; y > 5; y--) {
+				cacheX[o][y] = this.noiseX.func_151601_a(y * scaleV, (cz + 8 + o) * scaleH);
+				cacheZ[o][y] = this.noiseZ.func_151601_a((cx + 8 + o) * scaleH, y * scaleV);
+			}
+		}
+
+		for(int ox = 0; ox < 16; ox++) {
+			int x = cx + 8 + ox;
+
+			for(int oz = 0; oz < 16; oz++) {
+				int z = cz + 8 + oz;
+
+				double ny = this.noiseY.func_151601_a(x * scaleH, z * scaleH);
+
 				for(int y = 64; y > 5; y--) {
-					double nX = this.noiseX.func_151601_a(y * scaleV, z * scaleH);
-					double nY = this.noiseY.func_151601_a(x * scaleH, z * scaleH);
-					double nZ = this.noiseZ.func_151601_a(x * scaleH, y * scaleV);
-					
-					if(nX * nY * nZ > threshold) {
+					double nx = cacheX[oz][y];
+					double nz = cacheX[ox][y];
+
+					if(nx * ny * nz > threshold) {
 						Block target = world.getBlock(x, y, z);
-						
-						if(target.isNormalCube() && target.getMaterial() == Material.rock && target.isReplaceableOreGen(world, x, y, z, Blocks.stone)) {
+
+						if(target.isNormalCube() && target.isReplaceableOreGen(world, x, y, z, Blocks.stone)) {
 							world.setBlock(x, y, z, block, meta, 2);
 						}
 					}
@@ -88,4 +121,15 @@ public class OreLayer3D {
 			}
 		}
 	}
+
+	@SubscribeEvent
+	public void onWorldLoad(WorldEvent.Load event) {
+		alreadyDecorated.put(event.world.provider.dimensionId, new HashSet<>());
+	}
+
+	@SubscribeEvent
+	public void onWorldUnload(WorldEvent.Unload event) {
+		alreadyDecorated.remove(event.world.provider.dimensionId);
+	}
+
 }