diff --git a/src/webgl/loading.js b/src/webgl/loading.js
index 51eef5b09d..d9aed75215 100755
--- a/src/webgl/loading.js
+++ b/src/webgl/loading.js
@@ -629,6 +629,7 @@ function loading(p5, fn){
                   model.vertexColors.push(1);
                 } else {
                   hasColorlessVertices = true;
+                  model.vertexColors.push(-1, -1, -1, -1);
                 }
               } else {
                 face.push(usedVerts[vertString][currentMaterial]);
@@ -650,9 +651,8 @@ function loading(p5, fn){
     if (model.vertexNormals.length === 0) {
       model.computeNormals();
     }
-    if (hasColoredVertices === hasColorlessVertices) {
-      // If both are true or both are false, throw an error because the model is inconsistent
-      throw new Error('Model coloring is inconsistent. Either all vertices should have colors or none should.');
+    if (!hasColoredVertices) {
+      model.vertexColors = [];
     }
 
     return model;
diff --git a/test/unit/io/loadModel.js b/test/unit/io/loadModel.js
index f88a5807cc..590a12bb1e 100644
--- a/test/unit/io/loadModel.js
+++ b/test/unit/io/loadModel.js
@@ -79,11 +79,27 @@ suite('loadModel', function() {
     assert.deepEqual(model.vertexColors, expectedColors);
   });
 
-  test('inconsistent vertex coloring throws error', async function() {
-    // Attempt to load the model and catch the error
-    await expect(mockP5Prototype.loadModel(inconsistentColorObjFile))
-      .rejects
-      .toThrow('Model coloring is inconsistent. Either all vertices should have colors or none should.');
+  test('mixed material coloring loads model with sentinel colors for uncolored vertices', async function() {
+    const model = await mockP5Prototype.loadModel(inconsistentColorObjFile);
+    assert.instanceOf(model, Geometry);
+    assert.equal(
+      model.vertexColors.length,
+      model.vertices.length * 4,
+      'vertexColors should have four entries per vertex'
+    );
+    const hasSentinel = model.vertexColors.some(
+      (_, i) =>
+        i % 4 === 0 &&
+        model.vertexColors[i] === -1 &&
+        model.vertexColors[i + 1] === -1 &&
+        model.vertexColors[i + 2] === -1 &&
+        model.vertexColors[i + 3] === -1
+    );
+    const hasRealColor = model.vertexColors.some(
+      (_, i) => i % 4 === 0 && model.vertexColors[i] !== -1
+    );
+    assert.isTrue(hasSentinel, 'Uncolored vertices should have sentinel color');
+    assert.isTrue(hasRealColor, 'Colored vertices should retain their color');
   });
 
   test('missing MTL file shows OBJ model without vertexColors', async function() {