Commitment to Materials

　The bamboo used for “Raku-tei” is beautiful white bamboo that is roasted over a fire, soaked in oil, and then dried in direct sunlight. Since white bamboo is a natural bamboo material, it is inevitably damaged by insects such as longhorned beetles and bark beetles if it is left untreated. Therefore, we apply an insecticide treatment in which a highly effective insecticide is pressurized to penetrate into the interior of the bamboo material. The pressure is applied using a vacuum-pressurized injector, which removes the air contained in the bamboo fibers, allowing the chemical to penetrate to every corner of the interior. The insecticide is a highly effective, colorless, odorless, and safe bamboo-specific agent. Bamboo is also a material that is prone to mold. Therefore, we also provide a 24-hour flooding treatment with anti-bacterial and anti-fungal agents.

　In particular, the cut surfaces and inner surfaces of bamboo are areas prone to insect damage and fungal growth. Therefore, these areas are reinforced by applying a colorless, transparent liquid consisting mainly of a polyurethane prepolymer that easily permeates the bamboo at room temperature and pressure, and hardens by reacting with the water and cellulose in the bamboo tissue. This liquid does not contain toluene, xylene, or formaldehyde, which are harmful to the human body. This paint is safe and harmless to the human body.

　The wood is made of natural cedar and is cored to prevent splitting. Wood is susceptible to damage from insects and rotting fungi. ACQ is an environmentally friendly preservative made of copper and tetraammonium salt, and contains no arsenic or chromium compounds, making it a safe preservative and insecticide.

　In addition, wood protective impregnating paint is applied to protect the surface of the wood columns and to give them a textured color. Wood protective impregnating paint protects wood by effectively reflecting and absorbing ultraviolet rays. It also repels water and prevents it from seeping into the wood. Although these paints are highly protective, they do not create a coating film, so the wood’s excellent moisture control properties are not compromised and breathability is maintained. Thus, this paint has excellent weather resistance, water repellency, antisepsis, and mildew resistance, and allows the fragrance of the wood to be preserved.

　Raku-tei’s stone lanterns are made of Raitai-ishi stone produced in the Izumo region of Shimane Prefecture and are called Izumo-touro. The texture and coloring of Raitai-ishi stone are atmospheric, making it the ideal stone for the lanterns’ appearance. Raitsuseki is a tuffaceous sandstone formed by volcanic sediments deposited on the seafloor 14 million years ago (middle Miocene Neogene) from the Omori Raitsuseki Formation, which is found on the southern shore of Lake Shinji (around the Raitsuseki area in the town of Shishimicho, Matsue City). The Omori-Kuraitai Formation contains fossils of shark teeth, shellfish, trees, and other organisms and plants from the sedimentary period. 13-million-year-old fossils of Paleoparadoxia, a mammal that became extinct, have also been found. The Raitai Stone from the Omori-Raitai Formation has abundant reserves. The stone has been used as a high-quality stone material because of its uniform quality.
As early as around the 5th century (mid-Kofun period), it was used for stone chambers and sarcophagi in kofun tumuli (burial mounds).

　In the Middle Ages, it was used as a building material for stone pagodas (memorial and tombstones) such as Hokyointo and Gorinto, as well as for stone steps and stone walls. In the Edo period (1603-1867), raitai-ishi became known as gochiseki, a stone material that could only be sold outside the Matsue domain with the permission of the domain. Raitai-ishi was also used in Matsue Castle as a building material for stone steps and canal frames. It was also widely used for stone statues such as stone Buddhas, garden stones, and daily utensils.

In the late Edo period (1603-1867), various raitai stone products, including building materials, stone lanterns, komainu (stone guardian dogs), and Izumo karashishi (Izumo lion), were actively transported to all parts of Japan by the Japan Sea route and overland routes.

　Kimachi-ishi is still known today as the raw material for Izumo stone lanterns, a traditional handicraft designated by the national government, and for the glaze used in Ishu Tiles and Iwami Pottery, both of which utilize stone powder. It is also widely used for monuments such as statues and stone monuments, as well as building materials.

Oribe Lantern

　At Raku-tei, we mainly use two types of stone lanterns. One is the Oribe lantern. Oribe lanterns are said to have been conceived by Furuta Oribe, a tea master who was a disciple of Sen no Rikyu, the great master of Wabicha (tea ceremony). Because of their eccentric and distinctive appearance compared to other lanterns, they have been widely appreciated as tea ceremony room lanterns since the late Momoyama period (1573-1600). This is a square-shaped lantern with a fire box, which is mainly used as a bowl light in a stone washbasin. Therefore, they are mainly used in open-air tea gardens.

Yukimi lantern

　The other is Yukimi Lanterns. Yukimi lanterns are said to have been originally placed near water and enjoyed by admiring the lights reflected on the surface of the water, hence the name Yukimi Lanterns, which is a variation of Ukimi Lanterns. Therefore, yukimi lanterns are usually placed near the sea, rivers, or other watery places. Because of its rounded shape, the Yukimi Lantern is a heavy stone, yet it creates a delicate and gentle image. These lanterns are representative of the natural beauty of Japanese gardens, and are indispensable for expressing the natural beauty of the garden.

　Keiseki in Japanese gardens are set up to look like mountains or waterfalls. The stones used in Raku-teien are carefully selected for their texture, color, and shape from the outside. In the garden technique, the stones are placed in such a way that they appear large and calm. At Raku-tei, we cut the stones in such a way that their individual characteristics are maximized. Thus, simply by placing the stones, a magnificent landscape stone can stand in a perfect condition. If there are two or more landscape stones, it is important that the landscape stones balance each other. The entire garden should be united by the unified color and quality of the stones. Harmony is more important than the beauty of a single landscape stone. Therefore, a Japanese garden can tell a story as a whole.

　Gravel in Japanese gardens represents water, such as the sea or a river. In addition, to abstractly express the roughness of waves or the flow of a river, gravel is streaked with a broom. This is called a sand pattern. At Raku-teiwa, the grain size of natural stone gravel is standardized to approximately 3 mm so that visitors can enjoy drawing sand patterns. Three types of gravel are available. White gravel, which resembles pure white sand. Red coral gravel, which is an image of red color to ward off evil and bring good luck. Kinka gravel, which is inspired by the brown color of natural rivers and oceans with a golden hue. Sand painting is said to be a part of monks’ ascetic practices. Sand motifs can express the owner’s feelings as they are, such as a calm calm or a series of mystical rings. Sand motifs have the effect of calming and purifying the mind, and at the same time, they can be utilized and enjoyed in addition to viewing the rakutei.

　Every Japanese garden has a story intended by the gardener. Raku gardens, which represent a corner of the world, are of course designed with a clear story behind them. In particular, the Izumo-style garden series is based on the uniquely developed historical culture that is unique to the Izumo region of Shimane Prefecture. In addition, each garden feature, such as bamboo fences, lanterns, and stone wash basins, is created in keeping with the traditions handed down from generation to generation. Raku-tei is an assembled Japanese garden with a deep meaning that conveys the culture of the Japanese people to the present day against the backdrop of Japanese history.