diff --git a/haskoin-store-data.cabal b/haskoin-store-data.cabal
--- a/haskoin-store-data.cabal
+++ b/haskoin-store-data.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 4fafcd00b7d58feb5972201ca34b9c0654726c69f57b999b6eb365927f8941dd
+-- hash: ab67524bd0ec3464f66049a79f72633fac85730c7b5d781b5cdd50a5602528b4
 
 name:           haskoin-store-data
-version:        0.28.0
+version:        0.29.0
 synopsis:       Data for Haskoin Store
 description:    Data and its (de)serialisation functions for Haskoin Store
 category:       Bitcoin, Finance, Network
diff --git a/src/Haskoin/Store/Data.hs b/src/Haskoin/Store/Data.hs
--- a/src/Haskoin/Store/Data.hs
+++ b/src/Haskoin/Store/Data.hs
@@ -20,7 +20,7 @@
     , confirmed
 
       -- * Transactions
-    , BlockTx(..)
+    , TxRef(..)
     , TxData(..)
     , Transaction(..)
     , transactionToJSON
@@ -102,8 +102,8 @@
 import           Data.Word               (Word32, Word64)
 import           GHC.Generics            (Generic)
 import           Haskoin                 (Address, BlockHash, BlockHeader (..),
-                                          BlockHeight, BlockWork, KeyIndex,
-                                          Network (..), OutPoint (..),
+                                          BlockHeight, BlockWork, Coin (..),
+                                          KeyIndex, Network (..), OutPoint (..),
                                           PubKeyI (..), Tx (..), TxHash (..),
                                           TxIn (..), TxOut (..), WitnessStack,
                                           XPubKey (..), addrFromJSON,
@@ -222,27 +222,27 @@
             return MemRef {memRefTime = mempool}
 
 -- | Transaction in relation to an address.
-data BlockTx = BlockTx
-    { blockTxBlock :: !BlockRef
+data TxRef = TxRef
+    { txRefBlock :: !BlockRef
       -- ^ block information
-    , blockTxHash  :: !TxHash
+    , txRefHash  :: !TxHash
       -- ^ transaction hash
     } deriving (Show, Eq, Ord, Generic, Serialize, Hashable, NFData)
 
-instance ToJSON BlockTx where
-    toJSON btx = object ["txid" .= blockTxHash btx, "block" .= blockTxBlock btx]
+instance ToJSON TxRef where
+    toJSON btx = object ["txid" .= txRefHash btx, "block" .= txRefBlock btx]
     toEncoding btx =
         pairs
-            (  "txid" .= blockTxHash btx
-            <> "block" .= blockTxBlock btx
+            (  "txid" .= txRefHash btx
+            <> "block" .= txRefBlock btx
             )
 
-instance FromJSON BlockTx where
+instance FromJSON TxRef where
     parseJSON =
         A.withObject "blocktx" $ \o -> do
             txid <- o .: "txid"
             block <- o .: "block"
-            return BlockTx {blockTxBlock = block, blockTxHash = txid}
+            return TxRef {txRefBlock = block, txRefHash = txid}
 
 -- | Address balance information.
 data Balance =
@@ -331,6 +331,9 @@
     , unspentScript  :: !ShortByteString
     , unspentAddress :: !(Maybe Address)
     } deriving (Show, Eq, Ord, Generic, Hashable, Serialize, NFData)
+
+instance Coin Unspent where
+    coinValue = unspentAmount
 
 unspentToJSON :: Network -> Unspent -> Value
 unspentToJSON net u =
diff --git a/test/Haskoin/Store/DataSpec.hs b/test/Haskoin/Store/DataSpec.hs
--- a/test/Haskoin/Store/DataSpec.hs
+++ b/test/Haskoin/Store/DataSpec.hs
@@ -24,7 +24,7 @@
                                           bchRegTest, bchTest, btc, btcRegTest,
                                           btcTest, ripemd160, sha256)
 import           Haskoin.Store.Data      (Balance (..), BlockData (..),
-                                          BlockRef (..), BlockTx (..),
+                                          BlockRef (..), TxRef (..),
                                           DeriveType (..), Event (..),
                                           HealthCheck (..),
                                           PeerInformation (..), Prev (..),
@@ -55,7 +55,7 @@
         prop "identity for derivation type" $ \x -> testSerial (x :: DeriveType)
         prop "identity for xpub spec" $ \x -> testSerial (x :: XPubSpec)
         prop "identity for block ref" $ \x -> testSerial (x :: BlockRef)
-        prop "identity for block tx" $ \x -> testSerial (x :: BlockTx)
+        prop "identity for block tx" $ \x -> testSerial (x :: TxRef)
         prop "identity for balance" $ \x -> testSerial (x :: Balance)
         prop "identity for unspent" $ \x -> testSerial (x :: Unspent)
         prop "identity for block data" $ \x -> testSerial (x :: BlockData)
@@ -79,7 +79,7 @@
                 (balanceToJSON net)
                 (balanceToEncoding net)
                 x
-        prop "identity for block tx" $ \x -> testJSON (x :: BlockTx)
+        prop "identity for block tx" $ \x -> testJSON (x :: TxRef)
         prop "identity for block ref" $ \x -> testJSON (x :: BlockRef)
         prop "identity for unspent" . forAll arbitraryNetData $ \(net, x) ->
             testNetJSON
@@ -312,8 +312,8 @@
 instance Arbitrary TxId where
     arbitrary = TxId <$> arbitrary
 
-instance Arbitrary BlockTx where
-    arbitrary = BlockTx <$> arbitrary <*> arbitrary
+instance Arbitrary TxRef where
+    arbitrary = TxRef <$> arbitrary <*> arbitrary
 
 instance Arbitrary Hash160 where
     arbitrary = ripemd160 . pack <$> listOf1 arbitrary