diff --git a/src/ragged/_spec_set_functions.py b/src/ragged/_spec_set_functions.py
index 0ab8af6..259ccd9 100644
--- a/src/ragged/_spec_set_functions.py
+++ b/src/ragged/_spec_set_functions.py
@@ -64,10 +64,10 @@ def unique_all(x: array, /) -> tuple[array, array, array, array]:
             x_flat = ak.ravel(x._impl)  # pylint: disable=W0212
             if isinstance(x_flat.layout, ak.contents.EmptyArray):  # pylint: disable=E1101
                 return unique_all_result(
-                    values=ragged.array([]),
-                    indices=ragged.array([]),
-                    inverse_indices=ragged.array([]),
-                    counts=ragged.array([]),
+                    values=ragged.array(np.empty(0, x.dtype)),
+                    indices=ragged.array(np.empty(0, np.int64)),
+                    inverse_indices=ragged.array(np.empty(0, np.int64)),
+                    counts=ragged.array(np.empty(0, np.int64)),
                 )
             values, indices, inverse_indices, counts = np.unique(
                 x_flat.layout.data,  # pylint: disable=E1101
@@ -123,7 +123,8 @@ def unique_counts(x: array, /) -> tuple[array, array]:
             x_flat = ak.ravel(x._impl)  # pylint: disable=W0212
             if isinstance(x_flat.layout, ak.contents.EmptyArray):  # pylint: disable=E1101
                 return unique_counts_result(
-                    values=ragged.array([]), counts=ragged.array([])
+                    values=ragged.array(np.empty(0, x.dtype)),
+                    counts=ragged.array(np.empty(0, np.int64)),
                 )
             values, counts = np.unique(
                 x_flat.layout.data,  # pylint: disable=E1101
@@ -174,7 +175,8 @@ def unique_inverse(x: array, /) -> tuple[array, array]:
             x_flat = ak.ravel(x._impl)  # pylint: disable=W0212
             if isinstance(x_flat.layout, ak.contents.EmptyArray):  # pylint: disable=E1101
                 return unique_inverse_result(
-                    values=ragged.array([]), inverse_indices=ragged.array([])
+                    values=ragged.array(np.empty(0, x.dtype)),
+                    inverse_indices=ragged.array(np.empty(0, np.int64)),
                 )
             values, inverse_indices = np.unique(
                 x_flat.layout.data,  # pylint: disable=E1101
@@ -213,7 +215,7 @@ def unique_values(x: array, /) -> array:
         else:
             x_flat = ak.ravel(x._impl)  # pylint: disable=W0212
             if isinstance(x_flat.layout, ak.contents.EmptyArray):  # pylint: disable=E1101
-                return ragged.array([])
+                return ragged.array(np.empty(0, x.dtype))
             return ragged.array(np.unique(x_flat.layout.data, equal_nan=False))  # pylint: disable=E1101
     else:
         err = f"Expected ragged type but got {type(x)}"  # type: ignore[unreachable]