Inclusion deformation triggers fractures in the host

In her recent paper Marta Morana and co-authors stumbled on the least expected behavior for quartz inclusions trapped in garnet while exploring their behavior at high temperature conditions.

She was performing these experiments because the high-temperature behavior of quartz inclusions close to the alpha–beta transition boundary has not been studied experimentally in great detail on a large PT domain. These in situ high-temperature Raman spectroscopy on a quartz-in-garnet system up to 1000 K also contribute to improve the reference data set for the temperature dependence of the Raman scattering of free quartz.

Their results show that the alpha-to-beta phase transition is hindered by the stress imposed by the host on the quartz inclusion, resulting in a thermosalient effect of the whole host-inclusion system or a mechanical cracking of the host mineral.