diff --git a/aes/src/lib.rs b/aes/src/lib.rs
index ed562871..c9f1f605 100644
--- a/aes/src/lib.rs
+++ b/aes/src/lib.rs
@@ -65,7 +65,7 @@
 //! // Initialize cipher
 //! let cipher = Aes128::new(&key);
 //!
-//! let block_copy = block.clone();
+//! let block_copy = block;
 //!
 //! // Encrypt block in-place
 //! cipher.encrypt_block(&mut block);
diff --git a/aria/src/lib.rs b/aria/src/lib.rs
index 14a8f683..88d5ce98 100644
--- a/aria/src/lib.rs
+++ b/aria/src/lib.rs
@@ -18,7 +18,7 @@
 //! // Initialize cipher
 //! let cipher = Aria128::new(&key);
 //!
-//! let block_copy = block.clone();
+//! let block_copy = block;
 //! // Encrypt block in-place
 //! cipher.encrypt_block(&mut block);
 //! // And decrypt it back
diff --git a/cast5/src/lib.rs b/cast5/src/lib.rs
index 26dede16..16044019 100644
--- a/cast5/src/lib.rs
+++ b/cast5/src/lib.rs
@@ -18,7 +18,7 @@
 //! // Initialize cipher
 //! let cipher = Cast5::new(&key);
 //!
-//! let block_copy = block.clone();
+//! let block_copy = block;
 //! // Encrypt block in-place
 //! cipher.encrypt_block(&mut block);
 //! // And decrypt it back
diff --git a/cast6/src/lib.rs b/cast6/src/lib.rs
index 4c462c72..696743d1 100644
--- a/cast6/src/lib.rs
+++ b/cast6/src/lib.rs
@@ -18,7 +18,7 @@
 //! // Initialize cipher
 //! let cipher = Cast6::new(&key);
 //!
-//! let block_copy = block.clone();
+//! let block_copy = block;
 //! // Encrypt block in-place
 //! cipher.encrypt_block(&mut block);
 //! // And decrypt it back
diff --git a/speck/tests/mod.rs b/speck/tests/mod.rs
index bda26f68..905e0c1c 100644
--- a/speck/tests/mod.rs
+++ b/speck/tests/mod.rs
@@ -22,7 +22,7 @@ macro_rules! new_test {
             let ciphertext = hex!($ct_hex);
             let cipher = $cipher::new(&key.into());
 
-            let mut block = plaintext.clone().into();
+            let mut block = plaintext.into();
             cipher.encrypt_block(&mut block);
 
             assert_eq!(&ciphertext, block.as_slice());
diff --git a/twofish/tests/mod.rs b/twofish/tests/mod.rs
index eadd1cd0..aa324c58 100644
--- a/twofish/tests/mod.rs
+++ b/twofish/tests/mod.rs
@@ -17,9 +17,9 @@ macro_rules! new_test {
             for i in 1..50 {
                 let twofish = Twofish::new_from_slice(&key).unwrap();
 
-                let mut buf = plain.clone();
+                let mut buf = plain;
                 twofish.encrypt_block(&mut buf);
-                cipher = buf.clone();
+                cipher = buf;
                 twofish.decrypt_block(&mut buf);
                 assert_eq!(plain, buf);