diff --git a/WorldPainter/WPCore/src/main/java/org/pepsoft/worldpainter/tools/UpdateMaterials.java b/WorldPainter/WPCore/src/main/java/org/pepsoft/worldpainter/tools/UpdateMaterials.java
index ea230411..35e9cace 100644
--- a/WorldPainter/WPCore/src/main/java/org/pepsoft/worldpainter/tools/UpdateMaterials.java
+++ b/WorldPainter/WPCore/src/main/java/org/pepsoft/worldpainter/tools/UpdateMaterials.java
@@ -25,7 +25,8 @@ import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.Objects.requireNonNull;
 import static java.util.zip.ZipFile.OPEN_READ;
 import static org.pepsoft.minecraft.Constants.*;
-import static org.pepsoft.minecraft.Material.*;
+import static org.pepsoft.minecraft.Material.DIRT_PATH;
+import static org.pepsoft.minecraft.MaterialImporter.*;
 import static org.pepsoft.worldpainter.Constants.UNKNOWN_MATERIAL_COLOUR;
 
 @SuppressWarnings("ConstantConditions")
@@ -71,15 +72,6 @@ public class UpdateMaterials {
         }
     }
 
-    /**
-     * Guess whether a material receives light unto itself, despite being opaque to surrounding blocks.
-     */
-    private static boolean guessReceivesLight(String name) {
-        return NON_TRANSMITTING_TRANSPARENT_BLOCKS.contains(name)
-                || name.endsWith("_slab")
-                || name.endsWith("_stairs");
-    }
-
     private static void enrichMaterialsWithColours() throws IOException, ClassNotFoundException {
         Configuration config = Configuration.load();
         if (config == null) {
@@ -189,34 +181,6 @@ public class UpdateMaterials {
         }
     }
 
-    private static boolean guessVeryInsubstantial(String name) {
-        return guessVegetation(name) || name.contains("leaves");
-    }
-
-    private static boolean guessInsubstantial(String name) {
-        return guessVegetation(name);
-    }
-
-    private static boolean guessVegetation(String name) {
-        return (! name.endsWith("_block"))
-                && (! guessTreeRelated(name))
-                && (name.contains("leaf")
-                || name.contains("vine")
-                || name.contains("fungus")
-                || name.contains("roots")
-                || name.contains("azalea")
-                || name.contains("flowering")
-                || name.contains("lichen")
-                || name.contains("moss")
-                || name.contains("stem")
-                || name.contains("blossom"));
-    }
-
-    private static boolean guessNatural(String material) {
-        return (guessVegetation(material) || guessTreeRelated(material))
-                && (! material.contains("stripped"));
-    }
-
     public static ColourAndOrigin determineColour(Material material, JarFile jarFile) {
         material = PATCHES.getOrDefault(material.name, material);
         // Preserve the colours people are used to. TODO: some of these were temporary and are probably wrong!
@@ -360,6 +324,4 @@ public class UpdateMaterials {
         public final int colour;
         public final String origin;
     }
-
-    private static final Set<String> NON_TRANSMITTING_TRANSPARENT_BLOCKS = ImmutableSet.of(MC_DIRT_PATH, MC_GRASS_PATH);
 }
\ No newline at end of file