Abstract
The Mogok area in Myanmar is known for the occurrence of various gems, such as ruby, sapphire, spinel, topaz, tourmaline, etc.. Johachidolite; CaAl[B3O7] was first described by Iwase & Saito (1942) at the Johachido district, Kisshu Country, Kankyhokudo Prefecture, North Korea, and recently, was reported the occurrence of johachidolite from Mogok, Myanmar. This johachidolite is visually and chemically divided into two zones: light yellowish green colored (Th-rich zone) and orange colored (Th-poor zone). The genesis and formation condition will be discussed based on the chemical compositions of mineral paragenesis, cathodoluminescence (SEM-CL) images and microthermometry of fluid inclusions.
