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The chemical composition of the mineral ilmenite is useful in mineral exploration for diamonds and in understanding igneous geological processes. This study develops an analytical methodology for accurate analyses of ilmenite by LA-ICP-MS for major, minor, trace element and U–Pb isotopic compositions. Accuracy of chemical compositions by LA-ICP-MS is monitored by comparing with EMPA and accuracy of the LA-ICP-MS U–Pb ages is verified by comparison to published ages for other mineral geochrometers from the same sample. Variation of laser fluence (2, 3 and 5 J cm−2) and calibration materials (Mud Tank zircon, BCR-2g, and TB-1 rutile) are optimized to provide the best accuracy of ilmenite chemical and isotopic compositions. Rutile, as the primary calibration material for Pb/U ratios, produces accurate U–Pb ages within analytical uncertainties. Use of normalization to a 100% metal oxide total for LA-ICP-MS analyses, coupled with mineral stoichiometry calculations, allows for the estimation of Fe2+/Fe3+ ratios that compare well with similar estimates from EMPA (0.23 vs. 0.22 respectively). U–Pb age results from an igneous ilmenite from the Bushveld Complex using this methodology are within uncertainty of the zircon ID-TIMS age of the intrusion (2044 ± 31 Ma (2 s) vs. 2054.4 ± 1.3 Ma (2 s)).

Item Type:	Refereed Article
Keywords:	ilmenite, geochronology, U-Pb dating, LA ICPMS
Research Division:	Earth Sciences
Research Group:	Geology
Research Field:	Geochronology
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the earth sciences
UTAS Author:	Goemann, K (Dr Karsten Goemann)
UTAS Author:	Belousov, I (Dr Ivan Belousov)
UTAS Author:	Jenkins, K (Miss Kate Jenkins)
UTAS Author:	Danyushevsky, L (Professor Leonid Danyushevsky)
ID Code:	147343
Year Published:	2021
Web of Science® Times Cited:	5
Deposited By:	CODES ARC
Deposited On:	2021-10-27
Last Modified:	2022-07-08
Downloads:	4 View Download Statistics