The city of Itoigawa, Niigata Prefecture, is known as one of the world’s oldest jade-producing regions. Even today, it’s arguably the most notable location in Japan where jade can be found.
This is believed to be due to the city’s geological position, where the Fossa Magna and the Itoigawa-Shizuoka Tectonic Line meet. A plethora of minerals formed 20 to 500 million years ago were brought from the mountain ranges in the east, carried by such rivers as the Himekawa. As a result, many of these stones ended up on the coast of Itoigawa, often smoothed over by the current.
Nicknamed the Jade Coast, or Hisui Kaigan in Japanese, this coastline consists of pebbly beaches where rare minerals such as jadeite and nephrite can be found. Although it is strictly prohibited to pick jade in the Kotakigawa Jade Gorge, it is allowed on the Jade Coast. Up until the end of the 20th century, jade was so common on these beaches that the locals picked only high-quality specimens and returned the rest to the sea. It can be more difficult to find them today, but half a dozen (give or take) jadeite pebbles may be collected if one spends the whole day searching for them.
In 1994, the Fossa Magna Museum opened not very far from one of the beaches. Here, minerals from Itoigawa are exhibited, including many pieces of raw jadeite from the Jade Coast on display.