Norodom's palace was in brick and Wooden, but Sisowath's palace was in-built bolstered concrete by French architects, along with the murals in The brand new Chan Chhaya, Phochani and Throne Hall were completed by French artists. Norodom's Silver Pagoda was demolished and rebuilt in bolstered concrete while in the sixties, https://simonrvsni.wizzardsblog.com/26980334/facts-about-lsm99-revealed