  We present photometric observations from the {\it Stratospheric Observatory
for Infrared Astronomy (SOFIA)} at 11.1 $\mu$m of the Type IIn supernova (SN
IIn) 2010jl. The SN is undetected by {\it SOFIA}, but the upper limits
obtained, combined with new and archival detections from {\it Spitzer} at 3.6
\& 4.5 $\mu$m allow us to characterize the composition of the dust present.
Dust in other Type IIn SNe has been shown in previous works to reside in a
circumstellar shell of material ejected by the progenitor system in the few
millenia prior to explosion. Our model fits show that the dust in the system
shows no evidence for the strong, ubiquitous 9.7 $\mu$m feature from silicate
dust, suggesting the presence of carbonaceous grains. The observations are best
fit with 0.01-0.05 $\msun$ of carbonaceous dust radiating at a temperature of
$\sim 550-620$ K. The dust composition may reveal clues concerning the nature
of the progenitor system, which remains ambiguous for this subclass. Most of
the single star progenitor systems proposed for SNe IIn, such as luminous blue
variables, red supergiants, yellow hypergiants, and B[e] stars, all clearly
show silicate dust in their pre-SN outflows. However, this post-SN result is
consistent with the small sample of SNe IIn with mid-IR observations, none of
which show signs of emission from silicate dust in their IR spectra.
