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We report discoveries of 165 new quasar Ca  ii absorbers from the Sloan Digital Sky Survey (SDSS) Data Releases 7 and 12. Our c a  ii rest-frame equivalent width distribution supports the weak and strong subpopulations, split at |${W}^{\lambda 3934}_{0}=0.7$| Å. Comparison of both populations' dust depletion shows clear consistency for weak absorber association with halo-type gas in the Milky Way (MW), while strong absorbers have environments consistent with halo and disc-type gas. We probed our high-redshift Ca  ii absorbers for 2175 Å dust bumps, discovering 12 2175 Å dust absorbers (2DAs). This clearly shows that some Ca  ii absorbers follow the Large Magellanic Cloud (LMC) extinction law rather than the Small Magellanic Cloud extinction law. About 33 per cent of our strong Ca  ii absorbers exhibit the 2175 Å dust bump, while only 6 per cent of weak Ca  ii absorbers show this bump. 2DA detection further supports the theory that strong Ca  ii absorbers are associated with disc components and are dustier than the weak population. Comparing average Ca  ii absorber dust depletion patterns to that of Damped Ly α absorbers (DLAs), Mg  ii absorbers, and 2DAs shows that Ca  ii absorbers generally have environments with more dust than DLAs and Mg  ii absorbers, but less dust than 2DAs. Comparing 2175 Å dust bump strengths from different samples and also the MW and LMC, the bump strength appears to grow stronger as the redshift decreases, indicating dust growth and the global chemical enrichment of galaxies in the Universe over time. [ABSTRACT FROM AUTHOR]