diff --git a/montepy/data_inputs/material.py b/montepy/data_inputs/material.py
index d210fd4a..fb494f12 100644
--- a/montepy/data_inputs/material.py
+++ b/montepy/data_inputs/material.py
@@ -594,15 +594,12 @@ def append(self, nuclide_frac_pair: tuple[Nuclide, float]):
         self._check_valid_comp(nuclide_frac_pair)
         self._elements.add(nuclide_frac_pair[0].element)
         self._nuclei.add(nuclide_frac_pair[0].nucleus)
-        if not isinstance(nuclide_frac_pair[1], syntax_node.ValueNode):
-            node = self._generate_default_node(
-                float, str(nuclide_frac_pair[1]), "\n" + " " * DEFAULT_INDENT
-            )
-            syntax_node.ValueNode(str(nuclide_frac_pair[1]), float)
-            node.is_negatable_float = True
-            nuclide_frac_pair = (nuclide_frac_pair[0], node)
-        else:
-            node = nuclide_frac_pair[1]
+        node = self._generate_default_node(
+            float, str(nuclide_frac_pair[1]), "\n" + " " * DEFAULT_INDENT
+        )
+        syntax_node.ValueNode(str(nuclide_frac_pair[1]), float)
+        node.is_negatable_float = True
+        nuclide_frac_pair = (nuclide_frac_pair[0], node)
         node.is_negative = not self._is_atom_fraction
         self._components.append(nuclide_frac_pair)
         self._tree["data"].append_nuclide(("_", nuclide_frac_pair[0]._tree, node))
diff --git a/tests/test_material.py b/tests/test_material.py
index e580be69..da71a723 100644
--- a/tests/test_material.py
+++ b/tests/test_material.py
@@ -154,7 +154,7 @@ def test_material_deleter(_, big_material):
         assert old_comp[0] not in big_material
         old_comps = big_material[0:2]
         del big_material[0:2]
-        for nuc, _ in old_comps:
+        for nuc, _f in old_comps:
             assert nuc not in big_material
         with pytest.raises(TypeError):
             del big_material["hi"]