Machatschki (1928) correctly proposed that the feldspar structure is based on a framework of linked TO4 tetrahedra, but Taylor (1933) took the crucial step when he envisaged the actual topology of the framework structure on Christmas Day, 1932, followed by a comprehensive survey of the structural variants (Taylor et al., 1934). The pseudo-tetragonal structure proposed by Schiebold is wrong, but
... [Show full abstract] his X-ray measurements and some speculations were of temporary value (Schiebold, 1927; 1928; 1929a, b, c; 1930; 1931).