Fig. 2: Representative appearance and textures of the three gabbroic stones used in early 20th-century Japanese architecture.

Polished surfaces of gabbroic building stones: A Ukigane, B Nakoso, and C Matsuba (Susa). Crossed-polarized photomicrographs of the same stones: a Ukigane, b Nakoso, and c Matsuba. Scale bars: 9 mm for A–C, 1 mm for a–c.