Talk:Zircon

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What does "an age of 4.404 Ga" mean?

this should be: "an age of 4.404 x 10⁹years, this age is interpreted as crystallisation age " --Chd

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What does "(crystal class: 4/m 2/m 2/m)" mean? Could someone explain it or link to a new page for whatever this system is? -- Tarquin 20:36 Dec 29, 2002 (UTC)

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4/m 2/m 2/m is a tetragonal space group. It basically tells what symmetry elements can you expect in the zircon crystal structure. Some info is available at: http://www.uwgb.edu/dutchs/SYMMETRY/symmetry.htm http://www-structure.llnl.gov/xray/tutorial/spcgrp_tut.htm http://euch3i.chem.emory.edu/proposal/1b_space_groups.htm

[edit] Age incorrect?

The Narryer Gneiss Terrane says the Jack Hills zircons are 4.4 billion years old but this article says the oldest are 4.04. Isn't the older date correct? Badagnani 06:57, 24 July 2006 (UTC)

Er... I see 4.404 here not 4.04? Vsmith 11:35, 24 July 2006 (UTC)

Oh, good--I must have misread it! Thanks for the "second pair of eyes." Badagnani 05:45, 25 July 2006 (UTC)