Hailstone near Hondo may rank as one of the largest in Texas history A 3-D scan revealed the stone to be 6.4″ in diameter Published: Updated: Tags: There’s large hail and then there’s massive hail. In the case of a hailstone that fell near Hondo on April 28th, not only was it huge, it may have also been record-setting. The Insurance Institute for Business and Home Safety announced this week that a 3-D scan of the hailstone revealed it had a diameter of 6.4″. ”That stone is the largest one we ever scanned,” explained Dr. Tanya Brown-Giammanco, Managing Director of Research for the Insurance Institute for Business and Home Safety.