The invention relates to an ore used in a core tube of a water treatment device. The ore has six angles which are uniformly distributed at the periphery of the hexagonal ore. A concave part is formed between every two angles. A distance A from the center to the angle top is twice a distance B from the center to the angle bottom. The concave part is at an obtuse angle. The surface of the ore is provided with at least one through hole. The ore comprises the following components: medical stone used as a matrix, 10 to 15 percent of tourmaline, 50 to 68 percent of rare earth materials Nd2Fe14B, 18to 30 percent of granite, 1 to 2 percent of magnetite, 3 to 4 percent of zeolite and 1 to 0.5 percent of silver. The ore has an irregular shape, so the filling ratio is lower, the flow rate is not influenced, the impact direction of a water column is irregular and the water molecule energy field is naturally increased. Compared with the surface area of a spherical ore with the same density and weight as the hexagonal ore, the surface area of the hexagonal ore is nearly 20 percent larger than that of the spherical ore. Therefore, the impact area of water and the hexagonal ore is relatively superior to that of the water and the spherical ore. The impact area is larger, more water molecules are fragmentated and correspondingly the water molecule energy and the negative ion density can be higher.