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tokens: analyses of the strongly depleted element Ca have demonstrated that dust commonly reaches out far beyond the stellar bodies of galaxies deep into circumgalactic and intergalactic space (e.g., Richter et al. 2011 ; Zhu Ménard 2013 ). In this broader context, additional systematic studies of metal depletion in the MW halo and in other circumgalactic environments would be very useful to better understand the large-scale circulation of dust in and around galaxies. 5.3. Origin of LA II To further evaluate whether LA II originally stems from the SMC or LMC let us first collect the main results from our absorption-line study and summarize the main conclusions from these findings. 1. LA II exhibits an α abundance and N/ α ratio that closely match those of the current-day SMC, possibly implying that the gas was recently removed from the SMC and pushed deep into the MW halo. If so, the age of LA II can be at most a few hundred Myr. If we consider only the chemical abundance pattern as age indicator, LA II could be older if the gas originates in the LMC. In that case, the observed abundance pattern in LA II would reflect that of the LMC 1–2 Gyr ago (Pagel Tautvaisiene 1998 ; Harris Zaritsky 2004 ). That the LMC had exactly the same α /N abundance pattern as the SMC today at the time when the gas was removed from the MCs is not unrealistic given the star formation history of the LMC (Pagel Tautvaisiene 1998 ), but it would be a coincidence. 2. LA II exhibits a very high thermal gas pressure of P / k ≈ 1680 K cm −3 in the molecular gas phase, suggesting that the gas is situated in the inner halo of the MW ≈10 kpc above the disk, where the gas is compressed by ram-pressure forces. LA II and the MCs then would be separated by at least 30 kpc in space, suggesting that it would have taken the gas more than 200 Myr to reach its current position after it was separated from its host galaxy (assuming a relative speed of 100 km s −1 ). This sets a minimum age of ∼200 Myr for the LA II. Yet a distance a small as 10 kpc for the LA cannot be reproduced by the most recent hydrodynamical simulations of the Magellanic System (Pardy et al. 2018 ) in a first infall scenario, where the minimum distance of the LA is found to be d ≈ 24 kpc. 3. The H 2 formation timescale in the cold gas in LA II is ∼640 Myr. If all of the H 2 had formed in situ, this sets a lower limit for the age of the LA II. However, given the fact that so much dust has survived the separation process, it is equally likely that also the H 2 (or at least part of it) had formed earlier in the LA II source galaxy. If so, the H 2 was transported together with the neutral gas into the MW halo, where the molecular gas fraction adjusted to the local conditions on much shorter timescales. 4. The very high dust-to-gas ratio in LA II suggests that the gas originally stems from an interstellar region with a neutral+molecular gas column as high as log N (H) = 21.2. Such high column densities are typical for the inner