Fig. 2
From: Controlling salt deposition patterns using engineered substrates and thermal gradients

Evolution of a brine drop: evaporation and salt precipitation. (a) PTFE coated hybrid substrate made of glass and aluminum. (b) Homogeneous glass substrate with an imposed thermal gradient of 4.2 °C/cm. Salt precipitation starts on the cooler left side in both cases. The contact angle between brine and the PTFE substrate is ~ 110°. See time lapse Movies S1 and S2 in Supporting Information.