A method of preparing a mercury sorbent material comprising making a copper/clay mixture by admixing a dry clay and a dry copper source; making a sulfur/clay mixture by admixing a dry clay and a dry sulfur source; admixing the copper/clay mixture and the sulfur/clay mixture, to form a mercury sorbent pre-mixture; and shearing the mercury sorbent pre-mixture to form the mercury sorbent material. The mercury sorbent material has an interlayer d(001)-spacing of less than 12 Å when the mercury sorbent material contains less than 4 wt % water, and a powder X-ray diffraction pattern of the mercury sorbent material is substantially free of a diffraction peak at 2.73±0.01 Å, and the ζ-potential of the mercury sorbent material is greater than the ζ-potential of the dry clay.