Lit. mandala of the Adamantine Realm (Sk: Vajradhatu mandala). A mandala *mandara 曼荼羅 described in the Kongōchōkyō 金剛頂経 (Diamond Peak Sutra ; Sk: Sarvatathagatatattvasam graha). The Kongōchōkyō describes a total of 28 mandalas: six in Chapter one, ten in Chapter two, six in Chapter three, and six in Chapter four, and the Kongōkai mandara corresponds to the first of these, called the Kongōkai daimandara 金剛界大曼荼羅 (Great Mandala of the Adamantine Realm). The remaining 27 mandala are all variant or abbreviated forms of this mandala, and so it is the most important mandala described in the Kongōchōkyō. It is centered on *Dainichi 大日 displaying the *chiken-in 智拳印 mudra and is basically composed of the five *gochi nyorai 五智如来, sixteen great bodhisattvas jūroku daibosatsu 十六大菩薩, four paramita bodhisattvas shiharamitsu bosatsu 四波羅蜜菩薩, eight offering bodhisattvas hachikuyō bosatsu 八供養菩薩 and four guardian bodhisattvas shishō bosatsu 四摂菩薩, making a total of 37 deities, and these are known as the 37 deities of the Adamantine Realm Kongōkai sanjūshichison 金剛界三十七尊. These deities are divided into five groups or families, namely, Tathagata family nyoraibu 如来部 (Sk: tathagata-kula), Adamantine family kongōbu 金剛部 (Sk: vajra-kula), Jewel family hōbu 宝部 (Sk: ratna-kula), Lotus family rengebu 蓮華部 (Sk: padma-kula), and Action family katsumabu 羯磨部 (Sk: karma-kula), which occupy the center and four quarters of the mandala, thereby creating a format that is perfectly symmetrical both horizontally and vertically. This method of arranging deities was subsequently widely adopted in the specific mandalas *besson mandara 別尊曼荼羅 of Japan. The 28 mandalas described in the Kongōchōkyō were originally independent, but in China there evolved the *Kue mandara 九会曼荼羅 in which eight mandalas were arranged around the Kongōkai daimandara. This Kue mandara was introduced to Japan by *Kūkai 空海 (774-835), and in Japan it has come to be regarded as the standard form of the Kongōkai mandara, being used especially in the Shingon 真言 sect as one of the two mandalas forming the *Ryōkai mandara 両界曼荼羅. There are also, however, other versions of the Kongōkai mandara, including a 37-deity, Kongōkai sanjūshichison mandara zuzō 金剛界三十七尊曼荼羅図像 brought to Japan by Saichō 最澄 (766-822) (originally kept at Shōren'in 青蓮院, Kyoto, but now at the Metropolitan Museum of Art, New York), the *Kongōkai hachijūisson mandara 金剛界八十一尊曼荼羅 brought to Japan by Ennin 円仁 (794-864), and the *gobu shinkan 五部心観 brought to Japan by Enchin 円珍 (814-91). Among these different versions, the gobu shinkan contains all six mandala described in Chapter one of the Kongōchōkyō whereas the other two consist of only the Kongōkai daimandara. The Kongōkai hachijūisson mandara was used in the Tendai 天台 sect as one of the pair of Ryōkai mandara, but there are few other examples of its use and it was not widely employed.