黒漆白金物太刀 Kokushitsu Shirokanamono Tachi / Black Lacquer Silver Fittings Long Sword

What is Kokushitsu Shirokanamono Tachi in Japanese Katana terminology?

This is a long sword (Tachi) where the scabbard (Saya) is wrapped in leather made from animals like monkeys or horses, and then coated with black lacquer. The fittings such as the collar (Sekigane) and the chape (Kojiri) are made of silver.