“…15H to L) appearance. Reticulate coatings, characterized by their mesh-like structure and variable elemental contents (for example, Si, Mg, Al, Fe, Ca, Na, Cl and Mn), are known from hot spring deposits in the African Rift Valley (Casanova & Renaut, 1987;Casanova, 1994;Jones & Renaut, 1996a,c), hot spring deposits in New Zealand (McKenzie et al, 2001;Jones et al, 2003), in scale that lines pipes in the geothermal systems of Iceland (Gunnlaugsson & Einarsson, 1989;Kristmannsdottir et al, 1989;Sverrisdottir et al, 1992), submarine hot springs in Iceland (Geptner et al, 2002) and in speleothems found in wave-cut notches (Jones, 2010) and caves (L eveill e et al, 2000a,b;Polyak & G€ uven, 2000Polyak & G€ uven, , 2004. Their precise mineralogy is difficult to establish because they form such thin coatings that it is generally impossible to extract them for XRD analysis and most appear non-crystalline with microscale variations in element concentrations.…”