diff --git a/data/materials.dat b/data/materials.dat
index 3b2dbc28a..5f1517081 100644
--- a/data/materials.dat
+++ b/data/materials.dat
@@ -185,5 +185,7 @@
 "sea.rgb"                   N N    N    0.0    N     N    0.5   N   N   Y   Y
 "rock.rgb"                  N N    N    0.0    N     N    0.5   N   N   N   N
 "coniferous_tree.rgb"       Y Y    Y    0.5    N     N    0.5   N   N   N   N
- 
+"island/sky2.rgb"           N N    N    0.0    N     N    1.0   N   N   N   N
+"window.rgb"                N N    Y    0.0    Y     N    1.0   N   N   N   N
+
 # EOF #