  The 10 micron silicate feature is an essential diagnostic of dust-grain
growth and planet formation in young circumstellar disks. The Spitzer Space
Telescope has revolutionized the study of this feature, but due to its small
(85cm) aperture, it cannot spatially resolve small/medium separation binaries
(<3"; <420 AU) at the distances of the nearest star-forming regions (~140 pc).
Large, 6-10m ground-based telescopes with mid-infrared instruments can resolve
these systems. In this paper, we spatially resolve the 0.88" binary, UY Aur,
with MMTAO/BLINC-MIRAC4 mid-infrared spectroscopy. We then compare our spectra
to Spitzer/IRS (unresolved) spectroscopy, and resolved images from IRTF/MIRAC2,
Keck/OSCIR and Gemini/Michelle, which were taken over the past decade. We find
that UY Aur A has extremely pristine, ISM-like grains and that UY Aur B has an
unusually shaped silicate feature, which is probably the result of blended
emission and absorption from foreground extinction in its disk. We also find
evidence for variability in both UY Aur A and UY Aur B by comparing synthetic
photometry from our spectra with resolved imaging from previous epochs. The
photometric variability of UY Aur A could be an indication that the silicate
emission itself is variable, as was recently found in EX Lupi. Otherwise, the
thermal continuum is variable, and either the ISM-like dust has never evolved,
or it is being replenished, perhaps by UY Aur's circumbinary disk.
