Fig. 2.

Comparison of low-loss (A) and core-loss (B) electron energy loss spectra acquired from specimens overhanging holes in the support film (EELS collection half angle 2β = 6.34 ± 0.06 mrad). Shown are detonation synthesized nanodiamonds as well as graphene of supernova origin [Murchison meteorite (30)], of modern origin (charred fungal Sclerotium), and from the onset of the Younger–Dryas (Santa Rosa Island, CA). See Fig. 1 caption for expanded details. Arrows indicate peaks associated with π-π^∗ and 1s-2p(π^∗) sp² graphitic transitions as well as 1s-2p(σ^∗) sp³ diamond transitions.