Designed by the famed architect IM Pei, the Miho Museum was the dream of Mihoko Koyama (after whom it is named), the heiress to the Toyobo textile business, and one of the richest women in Japan. The museum houses her private collection of Asian and Western antiques, as well as other pieces with an estimated value of between US$300 million to US$1 billion. There are over two thousand pieces in total, of which approximately 250 are displayed at any one time. IM Pei’s design, which he came to call Shangri-La, is executed in a hilly and forested landscape. Approximately three-quarters of the 17,400 square meter building is situated underground, carved out of a rocky mountaintop. The roof is a large glass and steel construction, while the exterior and interior walls and floor are made of a warm beige-colored limestone from France – the same material used by Pei in the reception hall of the Louvre.