This paper, published in Nature Geoscience, reports on work we have done to recollect and re-examine material from the original Apex Chert microfossil locality.  Using a combination of paleontological (300 μm, as used in previous studies) and petrographic (30 μm) thin sections, we discovered that features nearly morphologically identical to previous described cyanobacterial fossils were instead secondary vein and fracture events scattered through out multiple phases in the rocks (see above).  Raman spectroscopic analyses revealed that these features are solid hematite, not carbonaceous, as had previously been reported.  This discrepancy, we feel, is due to two factors: (1) Raman point-spectroscopy is a surface technique, and the matrix overlying these features contains carbonaceous material and (2) hematite and carbonaceous matter each have a band very close to one another, and 3D confocal Raman spectroscopy has been done on these samples by making color-intensity maps from the most prominent band in the region in which carbonaceous matter is found, thus the hematite band could have been interpreted as a carbon band.  To request a pdf of this article, please click here.