Relationship between composition and d₀₀₁ for chlorite

The relationship between chemical composition and interplanar spacing d₀₀₁ for chlorite minerals has been determined by multiple regression analysis using data for 98 natural chlorite samples (trioctahedral, di,trioctahedral and dioctahedral). The regression equation is with the compositional variables as number of atoms per half formula unit, i.e., per O₁₀(OH)₈. The multiple R factor for the regression is 0.883, and the standard error of estimation is 0.032. The predictions from the equation above are compared with those from other equations formerly used, and it is concluded that the expression proposed here is best suited for chlorite compositions of the tri-, di,tri-, or dioctahedral series.