Donghai county, Niu Shan town, blue crystal business department. According to Baidu map, the business scope of Blue Sea Blue Crystal Business Department in Niu Shan Town, Donghai County includes crystal products, jewelry wholesale and retail, and sales of blue hair crystals. Donghai County is a county under the jurisdiction of Lianyungang City, Jiangsu Province. It borders Haizhou District of Lianyungang City in the east, Maling Mountain in the west, Shuyang County and Guanyun County in the south, and faces Ganyu District of Lianyungang City along Xinshu River in the northeast.