A sort of clay mineral bearing resemblance to rectorite is found in Chanling area, Suixian County, Hubei, Province. It occurs at the contact zone between metaholyokeite and albit-sericite phyllite as a product of alteration. It has irregular scaled shape, with G=2.79, H=2-3, Ng'=1.5494, and Np'=1.5436. The data obtained from such means as chemical analysis, X-ray diffraction，infrared absorption, thermal analysis and electron microscopy all indicate that this mineral is made up of alternate dioctahedral mica and dioctahedral smectite layers, having do60=1.503A，a0=5.20A，b0=9.02A and c0Sin β=24.70A。A good integral sequence of 001 diffraction obtained at room temperature suggests a regular interstratification, with δ=0.059 and VC=0. 239. Following are the formulae of dehydrated chemical structures: Mica-like layer: (K1.64Na0.41)2.05AL4[(Si6.08Al1.92)8O20]O2 smectite-like layer: (Ca0.53Mg0.16Na0.01K0.01H0.09)0.8(Al1.86Fe3+0.87Fe2+0.51Mg0.40Ti0.14)3.78[Si8O20]O2 The following experimental data of this mineral distinguish it from rectorite: 1. X.ray diffraction of the K-saturated sample shows d001=9.96A. 2. After being heated at 300℃, d001=9.83A. 3. Its water-saturated sample has d001=25.26A，showing only negligible eXPansion. 4. Its expanded layer has layer charge of 0.75, higher than that of recto- rite (0.3-0.6). It is thus tentatively considered that this mineral must be a muscovite/highly charged smectite (1:1) reg ularly,interstratified mineral.