Figure 1. Schematic of carbon classiﬁcation based on graphite. The classiﬁcation enabled the degree of crystal to be ranked (high to low) as graphite crystal > t-C > g-C > i-C. The i-C is highly disordered and approximates amorphous carbon (a-C). The isotropic carbon (i-C), graphitizable semiorder carbon (g-C), turbostratic carbon (t-C), and graphite panels were from a previous publication.1 Rhombohedral graphite panel was from http://www.bas.bg/cleps/events/see/Presentations/SED_07_Trifonova.pdf. Figure 2. Summary of the temperature gradient along the septa-sealed vial using our previous7 (center panel) and our optimized13 (right panel) methods. It also shows SEMs of the Zn deposits along the septa-sealed vials and of the AMS targets (GCI, GCIP) in the borosilicate inner vials. Our previous method produced AMS targets of gray-colored ICM 20% of the time and of GCI 80% of the time; neither target was a powder. Our optimized method13 produced AMS targets of 100% GCIP 100% of the time.13 AMS targets of GCIP produced more intense and reliable ion currents and more accurate Fm values than those of ICM or GCI. The left and center panels were from ref 13. The SEM picture (third from top, GCIP) in the right panel was also from ref 13. spherical, and the particle size of each was e37 µ m. The SEMs also showed the surface of ICM as featureless, of GCIP as uniform fuzz, and of GCI as nonuniform fuzz. Even though the SEMs alone did not distinguish between Fe3C crystal, i-C, g-C, t-C, and graphite Analytical Chemistry, Vol. 80, No. 20, October 15, 2008 7663