diff --git a/src/pymatlib/core/yaml_parser.py b/src/pymatlib/core/yaml_parser.py
index 31805bc6d486832ee73faeb77ef2b7f667c887b5..c9dd55aeec827a26002081c0e97a3b40c8b4e421 100644
--- a/src/pymatlib/core/yaml_parser.py
+++ b/src/pymatlib/core/yaml_parser.py
@@ -1031,7 +1031,7 @@ class MaterialConfigParser:
 # External Function
 ##################################################
 
-def create_alloy_from_yaml(yaml_path: Union[str, Path], T: Union[float, sp.Symbol]) -> Alloy:
+def create_alloy_from_yaml(yaml_path: Union[str, Path], T: Union[float, sp.Symbol]) -> Tuple[Alloy, np.ndarray]:
     """
     Create alloy instance from YAML configuration file
     Args: