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Round 2 of G-Chron: Report now complete and available for download


— the proficiency test for age-dating of minerals

One of the few ways to know if you can trust your U-Pb data

Round 2: G-Chron 2021 — Zircon Kara-18

The report for Round 2 containing results for Zircon Kara-18 is now available for download.

Round 1: G-Chron 2019 — Zircon Rak-17: Report available for download

The download procedure for all participants of G-Chron 2019 was detailed in a global email sent out on 10th April 2020. If you did not receive that email, check your junk/spam traps.

For enquiries about:

The programme and use of the website, contact Peter Webb and Michael Wiedenbeck: gchron.iag@gmail.com

Payments and subscriptions, contact Chris Jackson: iag-treasurer@virginmedia.com

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Your use of this website is subject to the terms and conditions of participation in G-Chron. By continuing you imply your acceptance of these terms and conditions.

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If your contact details have changed please update them. If your contact status or that of your colleagues has changed please email us, quoting your G-Chron account number.

G-Chron Organisers for the International Association of Geoanalysts:

Michael Wiedenbeck (Potsdam, Germany) Principal Organiser
Peter Webb (Milton Keynes, UK) Website Administrator
Chris Jackson (Ashford, UK) Subscriptions Manager


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