Some of the posters on this board who actually owned CLF's bonds ought to be able to help you pinpoint the historical prices of the various bonds that traded on the open market.
ps-I believe clf has a market correction quarterly;or shorties are lurking between ERs ready to quash your balls like stepping on grapes.Take a closer look of clf 2016 chart if you can and may the best man survive/win/$$$$$. ps2-use the $ you can effort to loose without loosing sleep.