We own the mountain.
Every road that carries our machines up the slope, we build and maintain ourselves. To own a mountain is not to hold a resource — it is to accept the duty of managing it, year after year. Only those who carry that duty can supply stone of this scale. This is where everything we deliver begins.
One word defines Oshima stone.
Monolith. Some of the largest granite blocks in Japan are quarried from this mountain. Keeping them in stock, cutting them, and setting them into architecture — few companies can carry a stone through all of it. This is why architects who place stone at the core of a space come to Ochihisa.
Everything stands on one island.
The quarry, the factory, the inspection yard, the stockyard, the office — all of it, on Oshima. Elsewhere, quarries, workshops and building sites lie far apart, and stone loses time with every move. Here, every process is completed within the island. The time we save becomes time our craftsmen spend facing the stone. The point of integration is not lower cost — it is concentration, the source of quality.
For every project, we build it twice.
At the inspection stage, Ochihisa assembles the stone exactly as it will stand in the finished architecture. Built once on Oshima, verified, then dismantled and shipped — what happens on site is the reproduction of a proven result. Installation is shorter, and the client sees the finished form with their own eyes before a single stone is set.
Wall inspection is where the difference is decisive. Most stone companies dry-fit walls lying flat on the ground. Ochihisa erects the wall on a steel frame and inspects it standing. A stone lying down and a stone standing up carry weight differently. Assembled under the same conditions as the actual installation, inspected at the same eye level as the finished work — this precision is why architects and general contractors, in Japan and beyond, entrust their stone to Ochihisa.
