The northwest coast of New Zealand's North Island is notable for its black sand beaches (formed by magnetite). This photograph of Lake Wainamu - just inland from Auckland's Bethell's Beach - at dusk provides a striking contrast: A black sand dune in the foreground, with a lake and tracts of native bush behind.
(December 30, 2014. Nikon D5000, 1/400s @ f/7.1, 20mm, ISO 200.)