Solid compsns. having cholesteric optical props. comprises (1) 30-95 wt.% esters of cholesterol or cholesterol-like sterols (e.g. lanosterol and isoandrosterone) in which the acid-derived moiety of each ester contains a 5-6C cyclic gp., contains =18C and is free of aliphatic chains of >4C, the esters including >=10% of >=1 half-ester of phthalic acid or phthalic acid substd. with =4 halo atoms or a NO2 gp; (2) =30 wt.% aliphatic esters of cholesterol or cholesterol-like sterol in which the aliphatic group has =18C; and (3) =50% cholesterol or cholesterol-like sterol, or the 3-halo derivs.