Micro-gabbro porphyry is a coarse-grained crystalline siliceous basalt with iso-granularconspicuous spots. Also known as micro-gabbrogabbro, micro-gabbro porphyry is mainly composed of plagioclase, ordinary pyroxenetitanium ordinary pyroxeneilmenite. Among them, the phenocrysts of plagioclase (formerly known as coarse-grained basalt) are particularly obvious, with a length of about 5 mm, but pyroxene crystals are microcrystalline, so it is named after micro-gabbro porphyry. The rocks are dark graygray-black. The sites where the micro-gabbro porphyry has been found include Tiantai Hill in Wangan Islet, Chuanfanyu on Jiangjiyuenyu, Dongjiyu, Jinguazaiyu, Goushazaiyu, Tongliang on Paisha Islet, Quzhaoyu,Suogang, Shanshuithe northeastern slopes of Gongbeishan in the main island of Magong City. The micro-gabbro porphyry in the field, such as Tiantai Hill, ChuanfanyuQuzhaoyu, is characteristic of compactupright plate-like joints, often showing a special landscape caused by a series of verticalhorizontalradial joints. Among them, the "Eye of Dongji" with the circular tubular micro-gabbro porphyry in Dongjiyuthe "Footprints of Immortals" in Tiantai Hill of Wang-an Township are the most famous. The specimens collected by this center are from Tiantai Hill of Wang-an Township.