diff --git a/crates/fj-core/src/validate/shell.rs b/crates/fj-core/src/validate/shell.rs
index fedf5cc72..20a4c966a 100644
--- a/crates/fj-core/src/validate/shell.rs
+++ b/crates/fj-core/src/validate/shell.rs
@@ -315,71 +315,11 @@ mod tests {
                 UpdateShell,
             },
         },
-        topology::{Curve, HalfEdge, Shell},
+        topology::{Curve, Shell},
         validate::{shell::ShellValidationError, Validate, ValidationError},
         Core,
     };
 
-    #[test]
-    fn curve_geometry_mismatch() -> anyhow::Result<()> {
-        let mut core = Core::new();
-
-        let valid = Shell::tetrahedron(
-            [[0., 0., 0.], [0., 1., 0.], [1., 0., 0.], [0., 0., 1.]],
-            &mut core,
-        );
-        let invalid = valid.shell.update_face(
-            &valid.abc.face,
-            |face, core| {
-                [face.update_region(
-                    |region, core| {
-                        region.update_exterior(
-                            |cycle, core| {
-                                cycle.update_half_edge(
-                                    cycle.half_edges().nth_circular(0),
-                                    |half_edge, core| {
-                                        let mut geometry = *core
-                                            .layers
-                                            .geometry
-                                            .of_half_edge(half_edge);
-                                        geometry.path = geometry.path.reverse();
-                                        geometry.boundary =
-                                            geometry.boundary.reverse();
-
-                                        [HalfEdge::new(
-                                            half_edge.curve().clone(),
-                                            half_edge.start_vertex().clone(),
-                                        )
-                                        .insert(core)
-                                        .set_geometry(
-                                            geometry,
-                                            &mut core.layers.geometry,
-                                        )]
-                                    },
-                                    core,
-                                )
-                            },
-                            core,
-                        )
-                    },
-                    core,
-                )]
-            },
-            &mut core,
-        );
-
-        valid
-            .shell
-            .validate_and_return_first_error(&core.layers.geometry)?;
-        assert_contains_err!(
-            core,
-            invalid,
-            ValidationError::CurveGeometryMismatch(..)
-        );
-
-        Ok(())
-    }
-
     #[test]
     fn half_edge_has_no_sibling() -> anyhow::Result<()> {
         let mut core = Core::new();
diff --git a/crates/fj-core/src/validation/checks/curve_geometry_mismatch.rs b/crates/fj-core/src/validation/checks/curve_geometry_mismatch.rs
index 36fc33f27..ea0ff191b 100644
--- a/crates/fj-core/src/validation/checks/curve_geometry_mismatch.rs
+++ b/crates/fj-core/src/validation/checks/curve_geometry_mismatch.rs
@@ -128,3 +128,80 @@ impl ValidationCheck<Shell> for CurveGeometryMismatch {
             .flatten()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        assert_contains_err,
+        operations::{
+            build::BuildShell,
+            geometry::UpdateHalfEdgeGeometry,
+            insert::Insert,
+            update::{UpdateCycle, UpdateFace, UpdateRegion, UpdateShell},
+        },
+        topology::{HalfEdge, Shell},
+        validate::Validate,
+        validation::ValidationError,
+        Core,
+    };
+
+    #[test]
+    fn curve_geometry_mismatch() -> anyhow::Result<()> {
+        let mut core = Core::new();
+
+        let valid = Shell::tetrahedron(
+            [[0., 0., 0.], [0., 1., 0.], [1., 0., 0.], [0., 0., 1.]],
+            &mut core,
+        );
+        let invalid = valid.shell.update_face(
+            &valid.abc.face,
+            |face, core| {
+                [face.update_region(
+                    |region, core| {
+                        region.update_exterior(
+                            |cycle, core| {
+                                cycle.update_half_edge(
+                                    cycle.half_edges().nth_circular(0),
+                                    |half_edge, core| {
+                                        let mut geometry = *core
+                                            .layers
+                                            .geometry
+                                            .of_half_edge(half_edge);
+                                        geometry.path = geometry.path.reverse();
+                                        geometry.boundary =
+                                            geometry.boundary.reverse();
+
+                                        [HalfEdge::new(
+                                            half_edge.curve().clone(),
+                                            half_edge.start_vertex().clone(),
+                                        )
+                                        .insert(core)
+                                        .set_geometry(
+                                            geometry,
+                                            &mut core.layers.geometry,
+                                        )]
+                                    },
+                                    core,
+                                )
+                            },
+                            core,
+                        )
+                    },
+                    core,
+                )]
+            },
+            &mut core,
+        );
+
+        valid
+            .shell
+            .validate_and_return_first_error(&core.layers.geometry)?;
+        assert_contains_err!(
+            core,
+            invalid,
+            ValidationError::CurveGeometryMismatch(..)
+        );
+
+        Ok(())
+    }
+}