We combine HST/NICMOS imaging photometry of the HR 4796A disk at previously unobserved wavelengths between 1.71-2.22micron with reprocessed archival observations to produce a measure of the dusts scattering efficiency as a function of wavelength. The spectrum of the dust, synthesized from the seven photometric measures, is characterized by a steep red slope increasing from 0.5 micron to 1.6 micron followed by a flattening of the spectrum at wavelengths $>$ 1.6 micron. We fit the spectrum with a model population of dust grains made of tholins, materials comprised of complex organic materials seen throughout the outer parts of our Solar System. The presence of organic material around a star that may be in the later stages of giant planet formation implies that the basic building blocks for life may be common in planetary systems.
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