Fig. summarizes a similar experiment for another graphite NP, with similar results, i.e., initial EEO2 near 10 -3 Da/O2 collision, fluctuation about that value as the NP lost ~13% of its initial mass, then increased substantially, to well above the initial EEO2, resulting in an additional ~22% decrease in M, followed by abruptly slowing of the rate by more than two orders of magnitude, followed by 6.5 hours of further slow decline in EEO2. It is conceivable that additional fast etching waves might have occurred if more time had been allowed, but in all the examples of graphitic NPs studied here and previously, we have never observed recovery of oxidation reactivity after periods of more than ~2 hours of nearinertness. The unique aspect of both graphite NPs, not seen for NPs of other carbon materials, was a substantial increase in EEO2 to well above the initial values, just prior to abrupt decreases by several orders of magnitude.