Latest News

Round 1 of G-Chron: Report now available


— the proficiency test for age-dating of minerals

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

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

The download procedure was detailed in a global email sent to all participants on 10th April. If you did not receive that email, check your junk/spam traps.

Postponement of G-Chron 2020

Due to delays in the preparation of the materials for Round 2 of the G-Chron programme, we will not be able to start this round in 2020.  Currently our best estimate for sample dispatch is around the middle of 2021.  We sincerely regret the delays that we are experiencing due to the current global health crisis.

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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You are required to have authorisation from G-Chron before you proceed and you are strictly limited to the use set out within that authorisation. Unauthorised access to or misuse of this system is prohibited and constitutes an offence under the Computer Misuse Act (UK) 1990.
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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