[Sr/Fe] as a function of [Fe/H] for the entire sample, compared to Johnson & Bolte (2002, J02 – orange asterisk), Barklem et al. (2005, B05 – black dots), the “First Stars” giants François et al. (2007, F07 – green  × , and dwarfs Bonifacio et al. (2009, B09 – purple  +, respectively. The dwarfs from our sample are shown as filled blue circles, while filled red triangles represent our giants. Three very enhanced stars are shown and labelled in this and the following figures: BD+17°3248 (Cowan et al. 2002, open black square), CS 22892–052 (Sneden et al. 2003, filled black triangle), and CS 31082–001 (Hill et al. 2002, also analysed in this study, hence the red triangle). Arrows indicate upper limits to the abundances. A flat trend of [Sr/Fe] is seen down to [Fe/H]  ~  −2.5, below which the scatter becomes dominant.