Abstract
A 7T wollastonite was found at Fuka, Okayama Prefecture. Based on film intensity data, its stacking sequence has been found as (TTGTGTG). Here, T represents a (100) slab of wollastonite which is in continuous position with respect to the preceding one, and G a slab displaced by b⁄2. The structure may be regarded as a mixed-layer structure composed of three 2M and one 1T. The structure gave R=0.13 for 65 hk0 reflexions observed. The lattice constants are a=54.3±0.3 Å, b=7.30±0.03 Å, c=7.08±0.03 Å, α=90.0±0.2°, β=95.5±0.2°, and γ=92.1±0.2°.
