diff --git a/df.materials.xml b/df.materials.xml
index b016f5ca8..6bbe9e90a 100644
--- a/df.materials.xml
+++ b/df.materials.xml
@@ -192,6 +192,7 @@
         <enum-item name='EVAPORATES'/>
         <enum-item/>
         <enum-item name='IS_CERAMIC'/>
+        <enum-item name='CARTILAGE'/> new in 50.0x
         <enum-item name='FEATHER'/>
         <enum-item name='SCALE'/>
         <enum-item name='HAIR'/>