diff --git a/Substrate/SubstrateCS/Source/AlphaBlock.cs b/Substrate/SubstrateCS/Source/AlphaBlock.cs
index d56c289..248a28e 100644
--- a/Substrate/SubstrateCS/Source/AlphaBlock.cs
+++ b/Substrate/SubstrateCS/Source/AlphaBlock.cs
@@ -184,7 +184,9 @@ namespace Substrate
         public AlphaBlock Copy ()
         {
             AlphaBlock block = new AlphaBlock(_id, _data);
-            block._tileEntity = _tileEntity.Copy();
+            if (_tileEntity != null) {
+                block._tileEntity = _tileEntity.Copy();
+            }
 
             return block;
         }
diff --git a/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs b/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
index 0176487..931154b 100644
--- a/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
+++ b/Substrate/SubstrateCS/Source/AlphaBlockCollection.cs
@@ -204,7 +204,10 @@ namespace Substrate
             SetID(x, y, z, block.ID);
             SetData(x, y, z, block.Data);
 
-            SetTileEntity(x, y, z, block.GetTileEntity().Copy());
+            TileEntity te = block.GetTileEntity();
+            if (te != null) {
+                SetTileEntity(x, y, z, te.Copy());
+            }
         }
 
         #region IBoundedBlockCollection Members