We present an analysis of the evolution of circumstellar dust and molecules in the environment of the very late thermal pulse object V4334 Sgr (Sakurais Object) over a $sim20$-year period, drawing on ground-, airborne- and space-based infrared photometry and spectroscopy. The dust emission, which started in 1997, resembles a blackbody that cooled from $sim1200$K in 1998 August to $sim180$K in 2016 July. The dust mass, assuming amorphous carbon, was $sim5times10^{-10}$M$_odot$ in 1998 August, and we estimate that the total dust mass was $sim2times10^{-5}$M$_odot$ by $sim2016$. The appearance of a near infrared excess in 2008 suggests a new episode of (or renewed) mass loss began then. We infer lower limits on the bolometric luminosity of the embedded star from that of the dust shell, which rose to $sim16000$L$_odot$ before declining to $sim3000$L$_odot$. There is evidence for weak 6-7$mu$m absorption, which we attribute to hydrogenated amorphous carbon formed in material ejected by Sakurais Object during a mass ejection phase that preceded the 1997 event. We detect small hydrocarbon and other molecules in the spectra, and trace the column densities in hydrogen cyanide (HCN) and acetylene (C$_2$H$_2$). We use the former to determine the $^{12}$C/$^{13}$C ratio to be $6.4pm0.7$, 14 times smaller than the Solar System value.
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