A procedure for the preparation of high-quality single crystals from concentrated glyme mixtures is presented. Anhydrous single crystals of LiNO3 and LiClO4 were prepared in this manner, and the single-crystal structure of LiClO4 (orthorhombic, Pnma, a = 8.6447(12) Angstrom, b = 6.8512(10) Angstrom, c = 4.8254(7) Angstrom, Z = 4) was determined as an example. This procedure is expected to be widely applicable for not only salts but also a wide range of other materials solvated by glymes.