Figure 1: Showing the location of the Zn 2p_1/2 (~1146 eV)  and the Zn 2p_1/2 (~1023 eV) peaks of a) a brass disc (BS002) has been cleaned (sonicated in micro 90 and water for 10 minutes), b) a brass disc (BS004) which had been corroded by fingerprint sweat for 24 hours and then cleaned, c) the same disc as in b) which was left in air for a further 15.5 hours d) the same disc in b) after being left in air for a further 65 hours. Data has been normalised by making the Zn 2p_3/2 equal to unity in each case.

One can see that there is a decrease in the Zn intensity, and potentially an increase intensity over time.