diff --git a/src/pymatlib/core/yaml_parser.py b/src/pymatlib/core/yaml_parser.py
index fc514fb1609acec232e57c5f3d052ddf9d95c2c0..2e806a82ace49bffcd7bae0db45462dc82eb3cc6 100644
--- a/src/pymatlib/core/yaml_parser.py
+++ b/src/pymatlib/core/yaml_parser.py
@@ -1032,7 +1032,7 @@ 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: