diff --git a/src/integrators/simple_random_integrator.rs b/src/integrators/simple_random_integrator.rs
index 5db972e..92308b3 100644
--- a/src/integrators/simple_random_integrator.rs
+++ b/src/integrators/simple_random_integrator.rs
@@ -55,11 +55,11 @@ impl Integrator for SimpleRandomIntegrator {
 }
 
 pub fn test_lighting_environment(w_o: &Vec3<f64>, wavelength: f64) -> f64 {
-    //let sun_direction = Vec3::new(1.0, 1.0, -1.0).normalize();
-    //if w_o.dot(&sun_direction) >= 0.99 {
-    //    300.0
-    //} else {
-    let sky_colour = ColourRgbF::new(w_o.y(), w_o.y(), 1.0);
-    Spectrum::reflection_from_linear_rgb(&sky_colour).intensity_at_wavelength(wavelength)
-    //}
+    let sun_direction = Vec3::new(1.0, 1.0, -1.0).normalize();
+    if w_o.dot(&sun_direction) >= 0.99 {
+        300.0
+    } else {
+        let sky_colour = ColourRgbF::new(w_o.y(), w_o.y(), 1.0);
+        Spectrum::reflection_from_linear_rgb(&sky_colour).intensity_at_wavelength(wavelength)
+    }
 }
diff --git a/src/main.rs b/src/main.rs
index fc6ae5c..d4349e1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,7 +16,7 @@ use std::time::Duration;
 use vanrijn::accumulation_buffer::AccumulationBuffer;
 use vanrijn::colour::{ColourRgbF, NamedColour, Spectrum};
 use vanrijn::image::{ClampingToneMapper, ImageRgbU8};
-use vanrijn::materials::LambertianMaterial;
+use vanrijn::materials::{LambertianMaterial, SmoothTransparentDialectric};
 use vanrijn::math::Vec3;
 use vanrijn::mesh::load_obj;
 use vanrijn::partial_render_scene;
@@ -122,13 +122,16 @@ pub fn main() -> Result<(), Box<dyn std::error::Error>> {
     println!("Loading object...");
     let mut model_object = load_obj(
         &model_file_path,
-        Arc::new(LambertianMaterial {
-            colour: Spectrum::reflection_from_linear_rgb(&ColourRgbF::from_named(
-                NamedColour::Yellow,
-            )),
-            diffuse_strength: 0.05,
-            //reflection_strength: 0.9,
-        }),
+        //Arc::new(LambertianMaterial {
+        //    colour: Spectrum::reflection_from_linear_rgb(&ColourRgbF::from_named(
+        //        NamedColour::Yellow,
+        //    )),
+        //    diffuse_strength: 0.05,
+        //    //reflection_strength: 0.9,
+        //}),
+        Arc::new(SmoothTransparentDialectric::new(
+            Spectrum::diamond_index_of_refraction(),
+        )),
     )?;
     println!("Building BVH...");
     let model_bvh: Box<dyn Primitive> =
@@ -149,6 +152,26 @@ pub fn main() -> Result<(), Box<dyn std::error::Error>> {
                         diffuse_strength: 0.1,
                     }),
                 )) as Box<dyn Primitive>,
+                Box::new(Plane::new(
+                    Vec3::new(1.0, 0.0, 0.0),
+                    -6.0,
+                    Arc::new(LambertianMaterial {
+                        colour: Spectrum::reflection_from_linear_rgb(&ColourRgbF::new(
+                            0.55, 0.27, 0.04,
+                        )),
+                        diffuse_strength: 0.1,
+                    }),
+                )),
+                Box::new(Plane::new(
+                    Vec3::new(0.0, 0.0, 1.0),
+                    12.0,
+                    Arc::new(LambertianMaterial {
+                        colour: Spectrum::reflection_from_linear_rgb(&ColourRgbF::new(
+                            0.55, 0.27, 0.04,
+                        )),
+                        diffuse_strength: 0.1,
+                    }),
+                )),
                 Box::new(Sphere::new(
                     Vec3::new(-6.25, -0.5, 1.0),
                     1.0,