diff --git a/src/gerbonara/graphic_primitives.py b/src/gerbonara/graphic_primitives.py
index 25ef3de..20f7634 100644
--- a/src/gerbonara/graphic_primitives.py
+++ b/src/gerbonara/graphic_primitives.py
@@ -121,14 +121,14 @@ class ArcPoly(GraphicPrimitive):
 
     def approximate_arcs(self, max_error=1e-2, clip_max_error=True):
         outline = []
-        for p1, p2, (clockwise, center) in self.segments():
+        for (x1, y1), (x2, y2), (clockwise, (cx, cy)) in self.segments:
             if clockwise is None:
-                outline.append(p1)
+                outline.append((x1, y1))
             else:
                 outline.extend(approximate_arc(cx, cy, x1, y1, x2, y2, clockwise,
                                                max_error=max_error, clip_max_error=clip_max_error))
                 outline.pop() # remove arc end point
-        return type(self)(outline)
+        return type(self)(outline, polarity_dark=self.polarity_dark)
 
     def bounding_box(self):
         bbox = (None, None), (None, None)
diff --git a/tests/test_primitives.py b/tests/test_primitives.py
index dc4b8ba..bf366fb 100644
--- a/tests/test_primitives.py
+++ b/tests/test_primitives.py
@@ -53,15 +53,21 @@ def object_test(tmpfile, img_support, epsilon=1e-4):
 
     # test primitive to_arc_poly
     arc_poly_gbr = GerberFile()
+    arc_poly_approx_gbr = GerberFile()
     for obj in gbr.objects:
         for primitive in obj.to_primitives(MM):
             poly = primitive.to_arc_poly()
             region = Region.from_arc_poly(poly)
             arc_poly_gbr.objects.append(region)
+
             # Regression test for gitlab issue #17
             assert primitive.polarity_dark == poly.polarity_dark
             assert region.polarity_dark == poly.polarity_dark
 
+            # Test for arc poly arc approximation, and regression test for gitlab issue #16
+            region = Region.from_arc_poly(poly.approximate_arcs())
+            arc_poly_approx_gbr.objects.append(region)
+
     arc_poly_svg = tmpfile('ArcPoly SVG Output', '.svg')
     with open(arc_poly_svg, 'w') as f:
         f.write(str(arc_poly_gbr.to_svg(force_bounds=bounds, arg_unit='inch', fg='black', bg='white')))
@@ -69,6 +75,14 @@ def object_test(tmpfile, img_support, epsilon=1e-4):
     arc_poly_png = tmpfile('ArcPoly conversion render', '.png')
     img_support.svg_to_png(arc_poly_svg, arc_poly_png, dpi=300, bg='white')
 
+    # Arc approximation test
+    arc_poly_approx_svg = tmpfile('ArcPoly Approximation SVG Output', '.svg')
+    with open(arc_poly_approx_svg, 'w') as f:
+        f.write(str(arc_poly_approx_gbr.to_svg(force_bounds=bounds, arg_unit='inch', fg='black', bg='white')))
+
+    arc_poly_approx_png = tmpfile('ArcPoly Approximation conversion render', '.png')
+    img_support.svg_to_png(arc_poly_approx_svg, arc_poly_approx_png, dpi=300, bg='white')
+
     # Reference export via gerber through GerbV
     out_gbr = tmpfile('GBR Output', '.gbr')
     gbr.save(out_gbr)
@@ -96,6 +110,11 @@ def object_test(tmpfile, img_support, epsilon=1e-4):
     assert mean < epsilon
     assert hist[3:].sum() < epsilon*hist.size
 
+    mean, _max, hist = img_support.image_difference(out_png, arc_poly_approx_png, diff_out=tmpfile('ArcPoly Approximation Difference', '.png'))
+    assert hist[9] < 1
+    assert mean < epsilon
+    assert hist[3:].sum() < epsilon*hist.size
+
 @pytest.mark.parametrize('angle_deg', [0, 5, -5, 10, -10, 15, -15, 30, -30, 45, -45, 60, -60, 75, -75, 90, -90, 120, -120, 180, 153, 155, 157])
 def test_line(angle_deg, tmpfile, img_support):
     with object_test(tmpfile, img_support) as gbr: