Because they are made of black volcanic sand rather than white coral sand or white quartz/limestone sand. However, Japan has also many white sand beaches, which are made of white coral sand (southern islands) and white quartz/limestone sand (peninsulas on mainlands).
White sand beaches in Japan:
http://www.Flickr.com/photos/ippei-janine/sets/72157600321338295/
There are also black sand beaches in volcanic countries such as Hawaii and Iceland.
The west coast sand is black because of its high iron content.
The Coast to Coast multi-sport race starts on Kumara beach on the west coast of the South Island of New Zealand and finishes on the beach in the suburb of Sumner in Christchurch city on the east coast.
The gold rush in New Zealand was primarily on their west coast. It started in 1864 and lasted until 1867.
The Southern Alps run up the west coast of the South Island.
near te henga beach in west auckland its also near a lake
Maui Dolphins are native to New zealand. They are only found in New Zealand waters, in a small section of the ocean just off the west coast of the North Island.
Iron-sand
On the west coast of New Zealand about 45km north of Greymoith.
The biggest Beach in New Zealand is Piha beach in the West coast in Auckland.
The Coast to Coast multi-sport race starts on Kumara beach on the west coast of the South Island of New Zealand and finishes on the beach in the suburb of Sumner in Christchurch city on the east coast.
Sand Masters - 2011 West Coast Warrior Dash 2-12 was released on: USA: 17 June 2012
West Coast, South Island, New Zealand!
Cape Lovitt is the westernmost point of New Zealand. It is located on the west coast of Auckland Island.
Because New Zealand is located in a temperate rainforest
Lake Kanieri is on the West Coast of the South Island of New Zealand. The closest township is Hokitika.
Mountains line the West Coast from the North Island to the South Island. West Coast remains Wet and leaves the East Coast prodominantly Dry and Warm.
The River Buller is on the West Coast of the South Island of New Zealand. It was named after Charles Buller who furthered the colonization of New Zealand.
California