They are occasionally called 'soft hail'. Ice pellets are quite moderate in size and are composed of clear ice, sometimes conical in shape. Hailstones are whitish in appearance and vary greatly in size. If a hailstone is cut open, a layered structure like an onion is sometimes apparent. A large hailstone may consist of several layers of clear and opaque ice.
Large hailstones fall from deep cumulonimbus clouds.
The cloud base may be 2,000 feet above the ground with tops at 30,000 feet. Much of the cloud will be composed of supercooled water droplets. As the hailstone falls it will collect tiny water droplets which freeze and form a layer of ice. Perhaps the hailstone will then be caught in a vigorous updraught. As it is carried back higher into the cloud, it collects more minute water or ice particles to form another layer of ice.