diff --git a/src/pymatlib/core/yaml_parser.py b/src/pymatlib/core/yaml_parser.py
index d7918a1f6546c01591db806ece7a4006d6c1e74c..ec2c895d37f465c53a191e1bf88fc65bd2b67376 100644
--- a/src/pymatlib/core/yaml_parser.py
+++ b/src/pymatlib/core/yaml_parser.py
@@ -1204,7 +1204,7 @@ 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: