Summary: Tables are given which enable a quick estimate to be made of the true thickness of kamacite plates from measurements of the Widmanstetter figure on a single random plane. The method is applied to the following meteorites (width in mm following name): Arispe, 2·90; Brenham, 0·91; Duketon, 1·13; Henbury, 0·74; Ogallala, 1·53; Thule, 0·89; View Hill, 0·62.