Zircon

Zircon is a durable zirconium silicate mineral that incorporates uranium when it forms but usually excludes lead, making it valuable for dating ancient rocks and preserving chemical records.

Uranium–lead dating: A radiometric dating method that uses the decay of uranium isotopes into lead isotopes to determine age. Uranium incorporated at crystallization decays into lead that can be measured in zircon.
Geochronology: The science of determining the ages and timing of geological events. Zircon is one of the most reliable minerals for dating ancient geological events.
Igneous rock: Rock formed when molten material cools and solidifies. Most zircon crystallizes from magma as igneous rocks cool.
Jack Hills zircons: Ancient detrital zircon grains found in Western Australia, including grains older than four billion years. Their ages and chemistry underpin major claims about Hadean crust and liquid water.
Zircon crystal structure: The tetragonal atomic arrangement of zirconium, silicon, and oxygen in zircon. Its structure accepts uranium and helps retain isotopic and chemical records.
Detrital zircon geochronology: The dating of zircon grains eroded from source rocks and deposited in sediment. Grain-age populations trace sediment sources and constrain the age of deposition.
Granite: A coarse-grained igneous rock composed mainly of quartz and feldspar. Granite commonly contains zircon crystals that can date its formation.
Acasta Gneiss: A tonalitic gneiss complex in Canada containing some of Earth’s oldest known rocks. Zircon grains from the complex help constrain the age of early continental crust.
Uranium–lead concordia diagram: A graph comparing ages calculated from two uranium–lead decay systems. Zircon analyses plot against concordia to reveal age agreement or disturbance.
Zircon saturation thermometry: A method for estimating magma temperature from zircon solubility in silicate melt. Zircon abundance and melt chemistry can record the temperatures of its host magma.

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