17th Sep 2012

Opalised fossils

Producing 97% of the world’s opals, Australia is practically the only place in the world where opalised fossils are found. Fossils are usually formed when plant or animal remains are buried after death, and are slowly encased with sediments and infused with minerals, leaving a rock-like replica of the original organic material. Opalised fossils, however, replace an organism’s organic material with shimmering, solid opal. Excellent detail can be preserved both on the surface and internally, depending on how the opal forms: it’s a hydrous silicon oxide, and begins as a solution of silica in water. If an organism completely rots away, the opal will fill the empty space and create a cast of the external features—but if an organism has left organic material behind, the solution might harden to form a replica of the internal structure too. One of the richest sources of opalised fossils is Lightning Ridge in northwestern New South Wales. The fossils paint a vibrant history of animals who lived there in the Early Cretaceous Period, approximately 110 million years ago—dinosaurs, marine reptiles, fish, early mammals, molluscs, plants… Unfortunately, the opalised fossils are often cut up for jewellery or sold overseas for their beauty and value, but as they’re of significant scientific interest, researchers and paleontologists are working to preserve them.

(Image Credit: 1, 2)

This post has 1,203 notes
  1. rainingapplesauce reblogged this from fluffmugger
  2. splash-the-cat reblogged this from thezelbinion
  3. thezelbinion reblogged this from tygermama
  4. helixsrambles reblogged this from ryttu3k
  5. salsa-ishida reblogged this from ryttu3k
  6. softseawhistle reblogged this from fluffmugger
  7. glass-cat reblogged this from ryttu3k
  8. imthehotfriend reblogged this from ryttu3k
  9. arkred reblogged this from fluffmugger
  10. ryttu3k reblogged this from fluffmugger and added:
    THESE ARE THE COOLEST AND I WANT ONE. I have a pyritised ammonite, but goddamn, opalised is so much cooler.
  11. lokisangelwithashotgun reblogged this from fluffmugger
  12. jaggedcliffs reblogged this from fluffmugger
  13. philstag reblogged this from fluffmugger
  14. tygermama reblogged this from fluffmugger
  15. fluffmugger reblogged this from sciencesoup and added:
    CAN WE JUST TALK ABOUT HOW AMAZING AND IMPORTANT THESE FUCKERS ARE? Generally there are two types of opalised fossils....
  16. aquilaaudax reblogged this from sciencesoup
  17. vihu reblogged this from sciencesoup
  18. drakmonster reblogged this from brazilian-mermaid
  19. brazilian-mermaid reblogged this from amysaurus
  20. amysaurus reblogged this from j33p3rscr33p3rs
  21. j33p3rscr33p3rs reblogged this from thesprocket
  22. vannamonster reblogged this from piddlyjunk
  23. piddlyjunk reblogged this from sciencesoup
  24. dardanos reblogged this from candygut