One of Japan’s Five Ryuseito Swords, Forged From Meteorites Roughly 130 years ago, a farmer in what’s now Japan’s Toyama Prefecture was digging for potatoes when he came across an unusual stone. Even appraisers from the Osaka mint couldn’t tell what it was, and it spent the next several years being used as a tsukemono ishi, basically a large stone placed on top of vegetables as part of the pickling process. However, this mysterious mineral was destined for greater things. In 1895, geologists from the Ministry of Agriculture and Commerce determined that the stone was a meteorite, which they would dub the Shirahagi Meteorite (Birch Meteorite). It was purchased by Enomoto Takeaki, a samurai who would go on to play a key role in the creation of Japan’s first modern navy and also serve as Minister of Communications, Education, Foreign Affairs, as well as two separate terms as Minister of Agriculture and Commerce. Instead of using the meteorite to make some pickles, Enomoto decided to use it to make some swords. Enlisting the services of swordsmith Okayoshi Kunimune, Enomoto commissioned five blades, two long swords and three tanto (literally “short swords,” but often closer in length to daggers) to be forged from the Shirahagi Meteorite. One of the tanto is housed at the Toyama Science Museum in Toyama City. Of the five meteorite blades, collectively known as the Ryuseito (literally “comet swords”), the higher quality of the two katana was presented by Enomoto to the current crown prince of Japan, who would later become Emperor Taisho, who reigned from 1912 to 1926. The remaining four were handed down to Enomoto’s descendants. The second katana is now owned by Tokyo University of Agriculture (which grew out of an institution Enomoto founded). As for the three tanto, one is in the possession of Ryugu Shrine in Otaru, on the island of Hokkaido, one’s whereabouts are unknown, and one is the blade seen here, kept as part of the Toyama Science Museum’s collection. Museum...