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https://www.academia.edu/95006467/Zircon_and_titanite_petrochronology_link_plutonism_volcanism_and_porphyry_copper_deposit_formation_in_the_Yerington_batholith_Nevada_USA (PDF) Zircon and titanite petrochronology link plutonism, volcanism and porphyry copper deposit... Zircon and titanite petrochronology link plutonism, volcanism and porphyry copper deposit formation in the Yerington batholith, Nevada, USA pdfzircontitanitevolcanismporphyry https://geology.com/minerals/titanite.shtml Titanite the mineral. Sphene the gemstone. Titanite is a rare calcium titanium silicate mineral. It is a minor ore of titanium and a gemstone known as sphene. the mineraltitanitesphenegemstone