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We have discovered two dusty intervening Mg  ii  absorption systems at   z ∼ 1.3  in the Sloan Digital Sky Survey (SDSS) data base. The overall spectra of both quasi‐stellar objects (QSOs) are red  ( u − K  &gt; 4.5 mag)  and are well modelled by the composite QSO spectrum reddened by the extinction curve from the Large Magellanic Cloud (LMC2) Supershell redshifted to the rest frame of the Mg  ii  systems. In particular, we detect clearly the presence of the ultraviolet (UV) extinction bump at  λ rest ∼ 2175 Å. Absorption lines of weak transitions like Si  ii λ1808, Cr  ii λ2056, Cr  ii + Zn  ii λ2062, Mn  ii λ2594, Ca  ii λ3934 and Ti  ii λ1910 from these systems are detected even in the low signal‐to‐noise ratio and low‐resolution SDSS spectra, suggesting high column densities of these species. The depletion pattern inferred from these absorption lines is consistent with that seen in the cold neutral medium of the LMC. Using the LMC   A   V    versus  N (H  i ) relationship, we derive  N (H  i )  ∼ 6 × 10 21  cm −2   in both systems. Metallicities are close to solar. Giant Metrewave Radio Telescope (GMRT) observations of these two relatively weak radio QSOs  (f ν ∼ 50 mJy)  resulted in the detection of 21‐cm absorption in both the cases. We show that the spin temperature of the gas is of the order of or smaller than 500 K. These systems provide a unique opportunity to search for molecules and diffuse interstellar bands at   z  &gt; 1 .

Detection of the 2175 Å extinction feature and 21‐cm absorption in two Mg ii systems at z ∼ 1.3