UASs have been under rapid development for applications in the mineral exploration industry, mainly for aeromagnetic surveying. They provide improved detection of smaller, deeper and weakly magnetic targets. A traditional system flying an altitude of 100m above ground level can detect a spherical ore body at a depth of 40m and magnetic susceptibility of 10-4, with a radius of ~16m. A UAS flying at 50m or 2m altitude AGL would require the radius to be 11m or 5m, respectively. Using the Venturer fixed-wing UAS and the SkyLance rotary-wing UAS, two aeromagnetic surveys were performed. The Venturer was stable in flight with a fourth difference noise level within industry standards of ±0.05nT. A magnetic map was produced showing local variations. The SkyLance flew over a zinc deposit with 3 magnetic anomalies. It produced repeatable data that compared well with upward continuation maps of ground magnetic data.