Hydrothermal Zircon

Numerous cases have been reported where zircon may have precipitated from a hydrothermal fluid or a fluid-saturated residual melt. Temperatures for hydrothermal zircon formation range from 600°C in late-magmatic systems at the magmatic-to-hydrothermal transition down to 300°C in mesothermal ore-forming systems. Late-magmatic to hydrothermal zircon may precipitate from fluid-saturated magma and possibly from the fluids exsolved from mineralized granites and pegmatites. For example, in the Sn–Wmineralized Mole Granite, New South Wales, Australia, zircon occurs in growth zones in hydrothermal quartz, along with monazite, xenotime and thorite