Louis Glick & Company, a manufacturer of gems and fine diamond jewelry, is offering the "Diamond Hourglass" as a prize during the Jewelers of America Show in New York. The timepiece-a genuine working hourglass-contains 35 cts. of uncut diamonds. Contestants enter to win by filling out an entry form provided in Louis Glick & Company's magazine advertising. The drawing will take place Feb. 6 at Louis Glick & Company's show booth. Louis Glick & Company, 1271 Avenue of the Americas, New York, NY 10020; (212) 259-0300, fax (212) 489-8280.