  Calcium Aluminium Inclusions (CAIs) formed in the Solar System, some 4,567
million years ago. CAIs are almost always surrounded by Wark-Lovering Rims
(WLRs), which are a sequence of thin, mono/bi-mineralic layers of refractory
minerals, with a total thickness in the range of 1 to 100 microns. Recently,
some CAIs have been found that have tektite-like bowl-shapes. To form such
shapes, the CAI must have travelled through a rarefied gas at hypersonic
speeds. We show how CAIs may have been ejected from the inner solar accretion
disc via the centrifugal interaction between the solar magnetosphere and the
inner disc rim. They subsequently punched through the hot, inner disc rim wall
at hypersonic speeds. This re-entry heating partially or completely evaporated
the CAIs. Such evaporation could have significantly increased the metal
abundances of the inner disc rim. High speed movement through the inner disc
produced WLRs. To match the observed thickness of WLRs required metal
abundances at the inner disc wall that are of order ten times that of standard
solar abundances. The CAIs cooled as they moved away from the protosun, the
deduced CAI cooling rates are consistent with the CAI cooling rates obtained
from experiment and observation. The speeds and gas densities required to form
bowl-shaped CAIs are also consistent with the expected speeds and gas densities
for larger, ~ 1 cm, CAIs punching through an inner accretion disc wall.
