Die cracks, die lines or clash marks?

They are cracks; will update with the OBV # from Snow once I get a chance. This obv. apparently paired with a Ty 1 reverse here and Ty 2 reverse(s). 1870 Cent Type I Rev Obv. 20: (RE) Die crack from the base of 18 to the rim at 7:00. Heavy die crack from the rim at 8:30 through UNIT and the bust point continuing in the field above the date parallel to the date. Also paired with S25 DDR, this example with at Ty I REV.I was looking at my 1870 Cent. It has two curved lines, which follow about the same path, one though the date and the second, longer line through the bust, to UNIT and to the rim. They don't appear to be cracks now that I look at them, as a crack should propogate through the letters and from the field through the bust... the lines stop at the letters and then continue on the other side! I know one of the listed cherrypicker's guide varieties has a curved die line though the head (don't have my guide handy--but it's not an 1870). CP Guide lists an 1865 with a curved line through the headress. Also, 1864 Snow 11 has circular lines on portrait.1870_1C_NG