Synthesis of silica aerogel for Cherenkov counters is being studied for more than 10 years at the Boreskov Institute of Catalysis in collaboration with the Budker Institute of Nuclear Physics. Index of refraction, light scattering length and light absorption length are optical characteristics which determine the quality of aerogel Cherenkov counter. These parameters were measured for the aerogel produced. The results are presented. (C) 2002 Elsevier Science B.V. All rights reserved.