diff --git a/src/bin/client/rpc/types/block.rs b/src/bin/client/rpc/types/block.rs
index ffb0f8042..138140f60 100644
--- a/src/bin/client/rpc/types/block.rs
+++ b/src/bin/client/rpc/types/block.rs
@@ -1,7 +1,7 @@
 use util::hash::*;
 use util::uint::*;
 
-#[derive(Serialize)]
+#[derive(Default, Serialize)]
 pub struct Block {
 	hash: H256,
 	#[serde(rename="parentHash")]
@@ -30,3 +30,12 @@ pub struct Block {
 	timestamp: u64
 }
 
+#[test]
+fn test_block_serialize() {
+	use serde_json;
+
+	let block = Block::default();
+	let serialized = serde_json::to_string(&block).unwrap();
+	println!("s: {:?}", serialized);
+	assert!(false);
+}