It is always difficult, and usually of questionable practicality, to attempt to judge contemporary standards of morality with those that existed thousands of years ago. Odysseus has to travel for over ten years to find his beloved family. he is dedicated to them.
Mrs. Radley dies
Scout believes that the world is ending because it is snowing and she has never seen snow before.
Jem and scout ran out of snow so they used mud as well.
One of my personal favorite heroes. He, unlike me, is extremely cultured. He, unlike me, follows the rules. He, very much like me, is incredibly sarcastic. He is also very empathetic and loyal. He possesses many classic hero traits, but the sarcasm really brought it all together to make him both inspiring and relatable.
Given the context and wording, I would say the iron weight is symbolizing a scale, or a like instrument used for weighing things such as potatoes or hay.