diff --git a/examples/files.js b/examples/files.js
index e4154ac2737611334313dee5d9d242ce9ca6caa4..70ddde841ded3dcbe008c3a90f2de8df190e3330 100644
--- a/examples/files.js
+++ b/examples/files.js
@@ -75,6 +75,7 @@ var files = {
 		"webgl_lines_sphere",
 		"webgl_loader_3ds",
 		"webgl_loader_3mf",
+		"webgl_loader_3mf_materials",
 		"webgl_loader_amf",
 		"webgl_loader_assimp",
 		"webgl_loader_assimp2json",
diff --git a/examples/js/loaders/3MFLoader.js b/examples/js/loaders/3MFLoader.js
index 1921fa515ee2ca5de889332094a338bcd407481b..e330c29ec2fca2cbe26621759134e7771c721df9 100644
--- a/examples/js/loaders/3MFLoader.js
+++ b/examples/js/loaders/3MFLoader.js
@@ -205,7 +205,35 @@ THREE.ThreeMFLoader.prototype = {
 
 		}
 
-		function parseBasematerialsNode( /* basematerialsNode */ ) {
+		function parseBasematerialsNode( basematerialsNode ) {
+
+			var basematerialsData = {
+				id: basematerialsNode.getAttribute( 'id' ), // required
+				basematerials: []
+			};
+
+			var basematerialNodes = basematerialsNode.querySelectorAll( 'base' );
+
+			for ( var i = 0; i < basematerialNodes.length; i ++ ) {
+
+				var basematerialNode = basematerialNodes[ i ];
+				var basematerialData = parseBasematerialNode( basematerialNode );
+				basematerialsData.basematerials.push( basematerialData );
+
+			}
+
+			return basematerialsData;
+
+		}
+
+		function parseBasematerialNode( basematerialNode ) {
+
+			var basematerialData = {};
+
+			basematerialData[ 'name' ] = basematerialNode.getAttribute( 'name' ); // required
+			basematerialData[ 'displaycolor' ] = basematerialNode.getAttribute( 'displaycolor' ); // required
+
+			return basematerialData;
 
 		}
 
@@ -437,7 +465,7 @@ THREE.ThreeMFLoader.prototype = {
 
 			if ( basematerialsNode ) {
 
-				resourcesData[ 'basematerial' ] = parseBasematerialsNode( basematerialsNode );
+				resourcesData[ 'basematerials' ] = parseBasematerialsNode( basematerialsNode );
 
 			}
 
@@ -514,39 +542,171 @@ THREE.ThreeMFLoader.prototype = {
 
 		}
 
-		function buildMesh( meshData ) {
+		function buildMesh( meshData, objects, modelData, objectData ) {
+
+			// geometry
 
 			var geometry = new THREE.BufferGeometry();
 			geometry.setIndex( new THREE.BufferAttribute( meshData[ 'triangles' ], 1 ) );
 			geometry.addAttribute( 'position', new THREE.BufferAttribute( meshData[ 'vertices' ], 3 ) );
 
-			if ( meshData[ 'colors' ] ) {
+			// groups
+
+			var basematerialsData = modelData[ 'resources' ][ 'basematerials' ];
+			var triangleProperties = meshData[ 'triangleProperties' ];
+
+			var start = 0;
+			var count = 0;
+			var currentMaterialIndex = - 1;
+
+			for ( var i = 0, l = triangleProperties.length; i < l; i ++ ) {
+
+				var triangleProperty = triangleProperties[ i ];
+				var pid = triangleProperty.pid;
+
+				// only proceed if the triangle refers to a basematerials definition
+
+				if ( basematerialsData && ( basematerialsData.id === pid ) ) {
+
+					if ( currentMaterialIndex === - 1 ) currentMaterialIndex = triangleProperty.p1;
+
+					if ( currentMaterialIndex === triangleProperty.p1 ) {
+
+						count += 3; // primitves per triangle
+
+					} else {
 
-				geometry.addAttribute( 'color', new THREE.BufferAttribute( meshData[ 'colors' ], 3 ) );
+						geometry.addGroup( start, count, currentMaterialIndex );
+
+						start += count;
+						count = 3;
+						currentMaterialIndex = triangleProperty.p1;
+
+					}
+
+				}
 
 			}
 
+			if ( geometry.groups.length > 0 ) mergeGroups( geometry );
+
 			geometry.computeBoundingSphere();
 
-			var materialOpts = {
-				flatShading: true
-			};
+			// material
+
+			var material;
+
+			if ( basematerialsData && ( basematerialsData.id === objectData.pid ) ) {
+
+				var materialIndex = objectData.pindex;
+				var basematerialData = basematerialsData.basematerials[ materialIndex ];
+
+				material = getBuild( basematerialData, objects, modelData, objectData, buildBasematerial );
+
+			} else if ( geometry.groups.length > 0 ) {
+
+				var groups = geometry.groups;
+				material = [];
 
-			if ( meshData[ 'colors' ] && 0 < meshData[ 'colors' ].length ) {
+				for ( var i = 0, l = groups.length; i < l; i ++ ) {
 
-				materialOpts[ 'vertexColors' ] = THREE.VertexColors;
+					var group = groups[ i ];
+					var basematerialData = basematerialsData.basematerials[ group.materialIndex ];
+
+					material.push( getBuild( basematerialData, objects, modelData, objectData, buildBasematerial ) );
+
+				}
 
 			} else {
 
-				materialOpts[ 'color' ] = 0xaaaaff;
+				// default material
+
+				material = new THREE.MeshPhongMaterial( { color: 0xaaaaff, flatShading: true } );
 
 			}
 
-			var material = new THREE.MeshPhongMaterial( materialOpts );
 			return new THREE.Mesh( geometry, material );
 
 		}
 
+		function mergeGroups( geometry ) {
+
+			// sort by material index
+
+			var groups = geometry.groups.sort( function ( a, b ) {
+
+				if ( a.materialIndex !== b.materialIndex ) return a.materialIndex - b.materialIndex;
+
+				return a.start - b.start;
+
+			} );
+
+			// reorganize index buffer
+
+			var index = geometry.index;
+
+			var itemSize = index.itemSize;
+			var srcArray = index.array;
+
+			var targetOffset = 0;
+
+			var targetArray = new srcArray.constructor( srcArray.length );
+
+			for ( var i = 0; i < groups.length; i ++ ) {
+
+				var group = groups[ i ];
+
+				var groupLength = group.count * itemSize;
+				var groupStart = group.start * itemSize;
+
+				var sub = srcArray.subarray( groupStart, groupStart + groupLength );
+
+				targetArray.set( sub, targetOffset );
+
+				targetOffset += groupLength;
+
+			}
+
+			srcArray.set( targetArray );
+
+			// update groups
+
+			var start = 0;
+
+			for ( i = 0; i < groups.length; i ++ ) {
+
+				group = groups[ i ];
+
+				group.start = start;
+				start += group.count;
+
+			}
+
+			// merge groups
+
+			var lastGroup = groups[ 0 ];
+
+			geometry.groups = [ lastGroup ];
+
+			for ( i = 1; i < groups.length; i ++ ) {
+
+				group = groups[ i ];
+
+				if ( lastGroup.materialIndex === group.materialIndex ) {
+
+					lastGroup.count += group.count;
+
+				} else {
+
+					lastGroup = group;
+					geometry.groups.push( lastGroup );
+
+				}
+
+			}
+
+		}
+
 		function applyExtensions( extensions, meshData, modelXml ) {
 
 			if ( ! extensions ) {
@@ -585,16 +745,42 @@ THREE.ThreeMFLoader.prototype = {
 
 		}
 
-		function getBuild( data, objects, modelData, builder ) {
+		function getBuild( data, objects, modelData, objectData, builder ) {
 
 			if ( data.build !== undefined ) return data.build;
 
-			data.build = builder( data, objects, modelData );
+			data.build = builder( data, objects, modelData, objectData );
 
 			return data.build;
 
 		}
 
+		function buildBasematerial( materialData ) {
+
+			var material = new THREE.MeshPhongMaterial( { flatShading: true } );
+
+			material.name = materialData.name;
+
+			// displaycolor MUST be specified with a value of a 6 or 8 digit hexadecimal number, e.g. "#RRGGBB" or "#RRGGBBAA"
+
+			var displaycolor = materialData.displaycolor;
+
+			var color = displaycolor.substring( 0, 7 );
+			material.color.setStyle( color );
+			material.color.convertSRGBToLinear(); // displaycolor is in sRGB
+
+			// process alpha if set
+
+			if ( displaycolor.length === 9 ) {
+
+				material.opacity = parseInt( displaycolor.charAt( 7 ) + displaycolor.charAt( 8 ), 16 ) / 255;
+
+			}
+
+			return material;
+
+		}
+
 		function buildComposite( compositeData, objects, modelData ) {
 
 			var composite = new THREE.Group();
@@ -634,22 +820,23 @@ THREE.ThreeMFLoader.prototype = {
 		function buildObject( objectId, objects, modelData ) {
 
 			var objectData = modelData[ 'resources' ][ 'object' ][ objectId ];
-			var meshData = objectData[ 'mesh' ];
 
-			if ( meshData ) {
+			if ( objectData[ 'mesh' ] ) {
+
+				var meshData = objectData[ 'mesh' ];
 
 				var extensions = modelData[ 'extensions' ];
 				var modelXml = modelData[ 'xml' ];
 
 				applyExtensions( extensions, meshData, modelXml );
 
-				objects[ objectData.id ] = getBuild( meshData, objects, modelData, buildMesh );
+				objects[ objectData.id ] = getBuild( meshData, objects, modelData, objectData, buildMesh );
 
 			} else {
 
 				var compositeData = objectData[ 'components' ];
 
-				objects[ objectData.id ] = getBuild( compositeData, objects, modelData, buildComposite );
+				objects[ objectData.id ] = getBuild( compositeData, objects, modelData, objectData, buildComposite );
 
 			}
 
diff --git a/examples/models/3mf/gear.3mf b/examples/models/3mf/gear.3mf
deleted file mode 100644
index a627c9e3f87fc8bd2b4924a25738ec270cba07bc..0000000000000000000000000000000000000000
Binary files a/examples/models/3mf/gear.3mf and /dev/null differ
diff --git a/examples/models/3mf/truck.3mf b/examples/models/3mf/truck.3mf
new file mode 100755
index 0000000000000000000000000000000000000000..6fc1daffabf2f9acd16957e907f46615c73a767a
Binary files /dev/null and b/examples/models/3mf/truck.3mf differ
diff --git a/examples/webgl_loader_3mf_materials.html b/examples/webgl_loader_3mf_materials.html
new file mode 100644
index 0000000000000000000000000000000000000000..eeaf5ffd1f19370d5f4e223952e5d252063f58c7
--- /dev/null
+++ b/examples/webgl_loader_3mf_materials.html
@@ -0,0 +1,158 @@
+<!DOCTYPE html>
+<html lang="en">
+	<head>
+		<title>three.js webgl - 3MF</title>
+		<meta charset="utf-8">
+		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
+		<style>
+			body {
+				color: #fff;
+				font-family:Monospace;
+				font-size:13px;
+				text-align:center;
+				background-color: #fff;
+				margin: 0px;
+				overflow: hidden;
+			}
+			#info {
+				position: absolute;
+				top: 0px; width: 100%;
+				padding: 5px;
+			}
+			a {
+				color: #ff0000;
+			}
+		</style>
+	</head>
+	<body>
+		<div id="info">
+			<a href="http://threejs.org" target="_blank" rel="noopener">three.js</a>
+			<a href="http://3mf.io" target="_blank" rel="noopener">3MF file with materials</a>
+		</div>
+
+		<script src="../build/three.js"></script>
+		<script src="js/loaders/3MFLoader.js"></script>
+
+		<script src="js/WebGL.js"></script>
+		<script src="js/controls/OrbitControls.js"></script>
+
+		<script src="js/libs/jszip.min.js"></script>
+
+		<script>
+
+			if ( WEBGL.isWebGLAvailable() === false ) {
+
+				document.body.appendChild( WEBGL.getWebGLErrorMessage() );
+
+			}
+
+			var camera, scene, renderer;
+
+			init();
+
+			function init() {
+
+				scene = new THREE.Scene();
+				scene.background = new THREE.Color( 0xa0a0a0 );
+				scene.fog = new THREE.Fog( 0xa0a0a0, 10, 500 );
+
+				scene.add( new THREE.AmbientLight( 0xffffff, 0.2 ) );
+
+				camera = new THREE.PerspectiveCamera( 35, window.innerWidth / window.innerHeight, 1, 500 );
+				camera.position.set( - 50, 40, 50 );
+				scene.add( camera );
+
+				//
+
+				var hemiLight = new THREE.HemisphereLight( 0xffffff, 0x444444 );
+				hemiLight.position.set( 0, 100, 0 );
+				scene.add( hemiLight );
+
+				var dirLight = new THREE.DirectionalLight( 0xffffff );
+				dirLight.position.set( - 0, 40, 50 );
+				dirLight.castShadow = true;
+				dirLight.shadow.camera.top = 50;
+				dirLight.shadow.camera.bottom = - 25;
+				dirLight.shadow.camera.left = - 25;
+				dirLight.shadow.camera.right = 25;
+				dirLight.shadow.camera.near = 0.1;
+				dirLight.shadow.camera.far = 200;
+				dirLight.shadow.mapSize.set( 1024, 1024 );
+				scene.add( dirLight );
+
+				// scene.add( new THREE.CameraHelper( dirLight.shadow.camera ) );
+
+				//
+
+				var loader = new THREE.ThreeMFLoader();
+				loader.load( './models/3mf/truck.3mf', function ( object ) {
+
+					object.quaternion.setFromEuler( new THREE.Euler( - Math.PI / 2, 0, 0 ) ); 	// z-up conversion
+
+					object.traverse( function ( child ) {
+
+						child.castShadow = true;
+
+					} );
+
+					scene.add( object );
+
+					render();
+
+				} );
+
+				//
+
+				var ground = new THREE.Mesh( new THREE.PlaneBufferGeometry( 1000, 1000 ), new THREE.MeshPhongMaterial( { color: 0x999999, depthWrite: false } ) );
+				ground.rotation.x = - Math.PI / 2;
+				ground.position.y = 11;
+				ground.receiveShadow = true;
+				scene.add( ground );
+
+				//
+
+				renderer = new THREE.WebGLRenderer( { antialias: true } );
+				renderer.setPixelRatio( window.devicePixelRatio );
+				renderer.setSize( window.innerWidth, window.innerHeight );
+				renderer.gammaOutput = true;
+				renderer.gammaFactor = 2.2;
+				renderer.shadowMap.enabled = true;
+				renderer.shadowMap.type = THREE.PCFSoftShadowMap;
+				document.body.appendChild( renderer.domElement );
+
+				//
+
+				var controls = new THREE.OrbitControls( camera, renderer.domElement );
+				controls.addEventListener( 'change', render );
+				controls.minDistance = 50;
+				controls.maxDistance = 200;
+				controls.enablePan = false;
+				controls.target.set( 0, 20, 0 );
+				controls.update();
+
+				window.addEventListener( 'resize', onWindowResize, false );
+
+				render();
+
+			}
+
+			function onWindowResize() {
+
+				camera.aspect = window.innerWidth / window.innerHeight;
+				camera.updateProjectionMatrix();
+
+				renderer.setSize( window.innerWidth, window.innerHeight );
+
+				render();
+
+			}
+
+			function render() {
+
+				renderer.render( scene, camera );
+
+			}
+
+		</script>
+	</body>
+</html>