diff --git a/cyclotomic.cabal b/cyclotomic.cabal
--- a/cyclotomic.cabal
+++ b/cyclotomic.cabal
@@ -1,5 +1,5 @@
 Name:                cyclotomic
-Version:             0.4
+Version:             0.4.1
 Synopsis:            A subfield of the complex numbers for exact calculation.
 Description:         The cyclotomic numbers are a subset of the
                      complex numbers that are represented exactly, enabling exact
diff --git a/src/Data/Complex/Cyclotomic.hs b/src/Data/Complex/Cyclotomic.hs
--- a/src/Data/Complex/Cyclotomic.hs
+++ b/src/Data/Complex/Cyclotomic.hs
@@ -211,10 +211,12 @@
 --   of the form @r * exp(2*pi*i*s)@; @polarRat r s@ is the same as @r * e q ^ p@,
 --   where @s = p/q@.
 polarRat :: Rational -> Rational -> Cyclotomic
-polarRat r s = fromRational r * e q ^ p
-    where
-      p = numerator s
-      q = denominator s
+polarRat r s
+    = let p = numerator s
+          q = denominator s
+      in case p >= 0 of
+           True  -> fromRational r * e q ^ p
+           False -> conj $ fromRational r * e q ^ (-p)
 
 -- | Complex conjugate.
 conj :: Cyclotomic -> Cyclotomic