ASSERT( item->quantity > 0);

        {

            beam.item_pos     = p;
            // Dropped item might have merged into stack
            if (is_stackable_item(*item))
            {
                for (stack_iterator si(p); si; ++si)
                {
                    if (items_stack(*item, *si))
                    {
                        beam.item_index = si->index();
                        break;
                    }
                }
            }
            else
                beam.item_index = igrd(p);
        }