Shirakawa-ishi is a famous white granite produced from Kyoto and used for gardening stonework. Its debris is called Shirakawa-suna and has been widely used in temple gardens of Kyoto as a traditional landscaping gravel due to its beautiful color. However, ever since the quarrying of Shirakawa-ishi was banned, landscapes made of Shirakawa-suna have been changing or lost. This study aimed to find out the color characteristics of Shirakawa-ishi and similar granites, and to discuss on appropriate substitutes for Shirakawa-suna. We collected Shirakawa-ishi from 3 quarries, and 4 similar granites of different origin. We analyzed the color of 3 main minerals (white feldspar, gray quartz, and black mica) in each sample by scanner, AutoCAD and Adobe Photoshop. The ratio of “white: gray: black” of Shirakawa-ishi was around 6.2:3:0.8, while the white-black contrast was strong, which lead to a soft white, but clear color. Compared to Shirakawa-ishi, Inada-ishi (Japan) was much lighter and showed greater black-white contrast, which was too white for landscaping gravel. The color of mica in SobuG603 (China) was unclear, while LeBlanc (France) was much darker and contained more quartz. Kitagi-ishi (Japan) was slightly darker in overall color, but closest to Shirakawa-ishi. Its debris was considered to be an appropriate substitute of Shirakawa-suna.
