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We present the column densities of heavy-elements and dust depletion studiesin twostrong Mg~II absorption systems at $z\sim1.4$ displaying the 2175-{\AA}dust extinction feature. Column densities are measured from low-ionizationabsorption lines using Apparent Optical Depth Method on the Keck/ESI spectra.We find the dust depletion patterns resemble to that of cold diffuse clouds inthe Milky Way (MW). The values, [Fe/Zn]$\approx -1.5$ and [Si/Zn]$<-0.67$, areamong the highest dust depletion measured for quasar absorption line systems.In another 2175-{\AA} absorber at $z$=1.64 toward the quasar SDSSJ160457.50+220300.5, Noterdaeme et al. (2009) reported a similar dust depletionmeasurement ([Fe/Zn]=$-1.47$ and [Si/Zn]=$-1.07$) and detected C~I and COabsorption lineson its VLT/UVES spectrum. We conclude that heavy dust depletion(i.e. a characteristic of cold dense clouds in MW) is required to produce apronounced 2175-{\AA} extinction bump.

High Dust Depletion in Two Intervening Quasar Absorption Line Systems with the 2175-{\AA} Extinction Bump at $z\sim1.4$