I came across this method for testing the hardness of lead on Youtube.
https://www.youtube.com/watch?v=HfsE...LOGZh6okRSgnK9
It only take a set of art pencils that are $7 on Amazon. There is a chart available and depending on what pencil will scratch the lead you can determine the hardness of the lead. The wheel weights I melted down were in the hardness range I thought they should be doing the pencil test but I would really like to see the results of a pencil test compared to an actual hardness tester to see how accurate the pencils are.