Zircon Gives Clues to Earth's Age, Wow!

[JewelFreak]

This is fascinating. The stone so small, I can't figure how anyone noticed it, let alone picked it up.

http://www.nbcnews.com/science/scie...ldest-known-piece-earth-scientists-say-n36916

 

[chrono]

I heard about it on NPR this morning and wondered the same thing.

 

[minousbijoux]

Truly amazing. I love science! I wish I understood more about what they knew to look for and how they knew a zircon was a result of the formation of the earth's crust...

 

[T L]

Is it treated for that color? LOL!

Seriously, what an amazing find, and I found another article on it.

http://www.pbs.org/wgbh/nova/next/earth/4-4-billion-year-old-crystal-is-the-oldest-piece-of-earths-crust/

 

[Kelli]

This is SO COOL. Thanks for sharing!

 

[LoversKites]

Very interesting. Thanks for posting about it here.

 

[MMtwo]

interesting, what an unusual looking crystal.

 

[wordie89]

Yup, in the wee small hours of the night I'm reading that article on ancient zircons and start thinking; yes, that's a very reasonable excuse for adding to my shiny sparkly collection...NOT! Seriously I have seen some pretty ones. Must set spinel...must set spinel...

 

[JewelFreak]

Yup, in the wee small hours of the night I'm reading that article on ancient zircons and start thinking; yes, that's a very reasonable excuse for adding to my shiny sparkly collection...NOT! Seriously I have seen some pretty ones. Must set spinel...must set spinel...

Oh yes, I know the feeling!

 

[dzop]

This is a common form of dating. Tiny zircons are fairly ubiquitous (IIRC, they form in felsic igneous rock), and are commonly preserved in sandstones and conglomerates ( alongside far more common quartz and feldspar crystals). Because zircons can incorporate uranium into their lattice, they are easy to date with very small samples, which allows for dating using laser ablation ICP-MS, which allows the researcher to use just a pin-prick sized sample. Under the microscope, zircons are distinct and recognizable, so the process is actually straightforward, if painstaking:

(1) go to the oldest sandstone you can find
(2) take samples
(3) have grad students comb the samples for zircon grains
(4) date each zircon
(5) hope one of the zircons comes out older than any previous zircon
(6) publish!

 

[JewelFreak]

And you make it sound so easy, Dzop! Thank you for the interesting info!