  Cassiopeia A, one of the most intriguing galactic supernova remnants, has
been a target of many observational efforts including most recent observations
by ALMA, Hubble, Herschel, Spitzer, NuSTAR, Integral, and other observatories.
We use recent gamma-ray lines observations of the radioactive products of Cas A
supernova explosive nucleosynthesis as well as spectral energy densities
derived for Cas A at infrared wavelengths to speculate about the possibility of
radioactive 44Ti being locked into large dust grains. This suggestion is also
supported by the possible observation of a pre-supernova outburst about 80
years before the actual Cas A supernova explosion in 1671 AD by Italian
astronomer G.D. Cassini. The plausibility of such a scenario is discussed also
with reference to recent supernovae, and to the contribution of core-collapse
supernovae to the overall dust production in the Galaxy.
