MATERIAL / AJI STONE

What is Aji stone?

Fine-grained granite from Aji and Mure, Kagawa.
A mountain landscape, held in a single stone.

Aji stone quarry panorama

THE DIAMOND OF GRANITE

A fine grain.
A quiet presence.

Closely interlocking crystals make a hard, weather-resistant stone. Polishing reveals fu mottling; splitting brings rich shadow.

Known as the “diamond of granite,” its beauty changes with the finish.

Large blocks in the quarry

THE CHARACTER OF AJI

One mountain. Many characters.

Light and shadow in a split face.

01 / SPLIT

SPLIT

Light and shadow in a split face.

Natural relief becomes the expression: rugged, yet delicate.

Time leaves its colour.

02 / PATINA

PATINA

Time leaves its colour.

Warm brown weathering meets grey stone. Each piece carries its own colour.

Layer by layer, a landscape.

03 / LAYER

LAYER

Layer by layer, a landscape.

Different grains and outlines come together in a rhythm of light and shadow.

Polishing reveals depth.

04 / POLISH

POLISH

Polishing reveals depth.

Fine grain and subtle fu mottling reveal a quiet depth in changing light.

Crystals and a split face revealed through quarrying
Mountain time becomes a surface we can touch.

80 MILLION YEARS / ONE STONE

Vast time.
Within reach.

About 80 million years ago, magma cooled slowly underground, allowing crystals to grow into Aji stone. Uplift and erosion exposed the rock that we quarry today.

A stone holds more than colour and pattern. Bringing this natural material into a space also brings an immense history into everyday life.

Read how stone forms

SELECTED FROM THE MOUNTAIN

Not every part of the mountain becomes a product.

Extracted stone is assessed for defects, fractures, dimensions and grain. Character varies within the mountain, and only some pieces meet the requirements of a particular product.

Why only a few tonnes may be selected from 100.

AJI / MURE — MANY HANDS, ONE STONE

One stone.
Many hands.

Aji stone quarry with its rock face and machinery

One of Japan’s three major stoneworking centres.

As of 2026, more than 200 stone-related businesses are based in Aji and Mure, Takamatsu, close to the quarries. Alongside Makabe in Ibaraki and Okazaki in Aichi, this is one of Japan’s three major stoneworking centres.

Quarriers, cutters, carvers and finishers each bring their own expertise. Work passes from hand to hand to create a single piece. Aji stone’s character comes not only from the mountain, but from this community of specialists.

KagawaAichiIbaraki
Aji–Mure / Okazaki / Makabe

A LIVING TRADITION

Centuries of craft.
Alive in every stone.

The history of Aji stone quarrying is traced back to the Heian period. It is associated with the construction of Takamatsu Castle beginning in 1588 and developed further as a quarry serving the Takamatsu domain in the Edo period.

Tools have changed, but the eye that reads the stone and the hand that checks its finish remain essential. Skills passed down over centuries now reach architecture, gardens and interiors.

Historical photograph of stoneworkers quarrying beneath a rock face

OOCHOUBA / 大丁場

From a domain quarry to the present.

A chōba is a place where stone is quarried. Northwest of Mount Goken, Oochouba has a history of supplying stone to the Matsudaira family of the Takamatsu domain during the Edo period. Its stone was used for work on Takamatsu Castle, as well as gravestones and lanterns associated with the domain’s lords.

According to the quarry operator’s account, the site passed to the Ōkubo family of the former Takamatsu domain after the abolition of the domains in the Meiji era; the name Oochouba came into use around that time. Reading the mountain, selecting stone and passing it to the next craftsperson remain living work here.

Schematic map of quarry areas and the coastal stoneworking district in Aji and Mure
01 Oochouba / 02 Nakachouba03 Aji / 04 NoyamaTeal: stoneworking district
From mountain quarries to coastal workshops: a closely connected stoneworking region.© OpenStreetMap contributors

FROM HAND TO HAND

Expertise, passed from hand to hand.

Quarrying, splitting, sawing, carving, finishing and installation: specialists collaborate to make a piece. This is a typical sequence; the steps vary with its intended use and finish.

  1. 01

    Quarrying

    Reading grain and fractures, quarriers select and extract a block from the mountain.

  2. 02

    Splitting

    Rows of drilled holes receive wedges. The stone is split along its grain into workable blocks.

  3. 03

    Sawing

    Diamond saws cut the block to the required dimensions and thickness, with attention to the grain.

  4. 04

    Shaping & carving

    Machines and chisels shape outlines and details, from lantern components to architectural elements.

  5. 05

    Surface finishing

    Polishing reveals mottling; tooling creates texture. Each finish responds to light, touch and setting.

  6. 06

    Installation

    Finished pieces travel to the site, where careful positioning and fitting bring the work into the space.

  7. 07

    Complete

    A stone from the mountain becomes part of a garden or building. A new chapter begins in everyday life.

From stone to space ↗

NO TWO ALIKE

No two alike.
That is the pleasure of choosing.

Grain, mottling and weathering vary. Together, we look at the actual stone to find the piece that belongs in your space.

Light and shadow on the rock face
Fine crystals on a split Aji stone surface
Dense grain on cut stone
A sharp edge and rugged split face
A piece of stone with subtle warm weathering
A massive quarry rock face
Looking up through the Aji quarry
Freshly extracted Aji stone blocks

TEXTURES

From stone to fabric. Expression expands.

STONE Raw stone & forms ↗FABRIC Wear stone ↗