diff --git a/consensus/ethash/consensus.go b/consensus/ethash/consensus.go
index a248046f3f..e28ff896ad 100644
--- a/consensus/ethash/consensus.go
+++ b/consensus/ethash/consensus.go
@@ -34,12 +34,13 @@ import (
 	set "gopkg.in/fatih/set.v0"
 )
 
-// Ethash proof-of-work protocol constants.
+// Ethash proof-of-work protocol constants
+// Callisto reward 600 CLO.
 var (
-	callistoBlockReward, _          = new(big.Int).SetString("10000000000000000000", 10) // Block reward in wei for successfully mining a block
-	FrontierBlockReward    *big.Int = big.NewInt(5e+18)                                  // Block reward in wei for successfully mining a block
-	ByzantiumBlockReward   *big.Int = big.NewInt(3e+18)                                  // Block reward in wei for successfully mining a block upward from Byzantium
-	maxUncles                       = 2                                                  // Maximum number of uncles allowed in a single block
+	callistoBlockReward, _          = new(big.Int).SetString("600000000000000000000", 10) // Block reward in wei for successfully mining a block
+	FrontierBlockReward    *big.Int = big.NewInt(5e+18)                                   // Block reward in wei for successfully mining a block
+	ByzantiumBlockReward   *big.Int = big.NewInt(3e+18)                                   // Block reward in wei for successfully mining a block upward from Byzantium
+	maxUncles                       = 2                                                   // Maximum number of uncles allowed in a single block
 )
 
 // Various error messages to mark blocks invalid. These should be private to