656 views

Over 12,500 photos and growing!


  30 - September - 2017

This Month       Today's Picture       Select a Month

Submit a Picture

Where is My Picture?!

The Queue


Select by   Contributor

Met Name

Met Type

Thin Sections


Recent Comments


MISSING: 9.04 kilogram Sikhote-Alin shrapnel individual   More Info


 
Moldavite   contributed by Bernd Pauli   MetBul Link


Roll Overs:     #1   #2    


Click the picture to view larger photos

View all entries for   Meteorite (20)   Contributor (91)


Copyright (c) Bernd Pauli.
2.9 grams.   Impactite

Bernd writes:
Moldavites are silica-rich natural glasses that were produced when a cosmic impactor excavated the Ries Basin (Noerdlinger Ries) in Germany about 14.415.1 Ma ago. The Ries Crater has a diameter of 24 km and the impacting object must have measured hundreds of metres in diameter. While Australasian tektites are black, moldavites are green and highly translucent probably due to their relatively low content of titanium. The MPOD moldavite shown here is a rare example of a bi-colored moldavite.

Whereas Trnka, Houzar (2002), and Dehner (2009) are of the opinion that such moldavites are the result of collision of molten moldavites during flight, Michael Hurtig in his recently published book on Lusatian moldavites (2017) envisions a different scenario. On page 160 he writes that bi-colored moldavites are the result of primarily inhomogenous glass melts and that the sediments from which they formed must have consisted of several different components that were not completely molten and thus not homogenized. Such a process would provide an easy explanation for the color changes and would also be in accordance with the gradual, diffuse change of color that can be observed in my bi-colored specimen. The central part of this rod-shaped moldavite is green whereas the rim areas are brownish olive.


  Click to view larger photos     Photo 1     Photo 2
 


Comment on this MPOD                      
Name
Comment

980 max length

  Please - NO Dealer Ads in the comments
but pictures from dealers are gladly accepted

Tomorrow

Henbury
Matthias Baermann

This Month

Jansen Lyons
 9/30/2017 9:33:55 AM
Great piece Bernd! Nice history and explanation for the colors, very interesting! Cheers!
Daniel Da Costa
 9/30/2017 6:22:16 AM
good
Twink Monrad
 9/30/2017 4:50:37 AM
So delicate and beautiful Interesting theories on colors
 

Hosted by
Tucson Meteorites
Server date and time
1/27/2022 8:41:34 PM
Last revised
1/18/22
Terms of Use Unsubscribe