Radial profile of GC metallicities in comparison to their photometric colours, the NSC, and the integrated galaxy light. Top: radial profile of the mean stellar metallicity (black line) with GCs (circles), UCD (diamond) and the NSC (star). The symbols are colour-coded by their (g − z) colours from Jordán et al. (2015) and Turner et al. (2012). Bottom: (g − z) colours of the photometric sample of GC candidates from Jordán et al. (2015) versus projected distance. The NSC and FCC 47-UCD1 are added and we mark the GCs for which we have spectroscopic metallicity measurements. The dotted line is the mean of GC colours in bins of 10 arcsec. The NSC colour is the colour within a 4-pixel aperture on the HST/ACS images (Turner et al. 2012). We also included the histogram of GC colours to illustrate the bimodal colour distribution.