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Thundereggs!

60 videos
Updated 1 month ago
Thundereggs are unique geological formations often confused with geodes or agates due to some similarities, but they possess distinct characteristics. Here's an in-depth look at thundereggs: Formation: Volcanic Origin: Thundereggs form within layers of rhyolitic volcanic ash or lava flows. They begin as gas bubbles or voids in the cooling lava, acting as molds. Mineral Deposition: Over millions of years, groundwater rich in silica percolates through these porous volcanic rocks. The silica precipitates out of solution, filling these cavities. This process can be cyclical, with different events leading to varied mineral compositions and patterns within the thunderegg. Slow Crystallization: The minerals crystallize slowly, often forming concentric layers of chalcedony, agate, jasper, or opal, sometimes with quartz or calcite crystals in the center. Characteristics: Shape: Generally spherical or ovoid, ranging from a few centimeters to over a meter in diameter, though most are about the size of a baseball. Exterior: Typically, thundereggs have a rough, bumpy, and unremarkable exterior, often appearing as ordinary rocks until cut open. Interior: When cut and polished, they reveal intricate patterns, colors, and sometimes landscapes of agate, jasper, or other minerals. Unlike geodes, thundereggs may not be hollow; they are usually filled or have only small cavities. Composition: The core can consist of various minerals, leading to a wide variety of appearances. The outer shell is generally rhyolite or a similar volcanic rock. Locations: Oregon, USA: Particularly famous for thundereggs, especially in areas like the Owyhee Canyonlands, Ochoco National Forest, and near Prineville, where it's even the state rock. Other Regions: They are also found in places like Germany, Mexico, Australia, and Brazil, but Oregon remains the most renowned source. Cultural and Historical Aspects: Naming: The name "thunderegg" reportedly comes from Native American legends where these formations were believed to be the eggs of thunderbirds, mythical creatures associated with storms and thunder. Collection: Thundereggs are highly sought after by rock collectors, lapidaries, and enthusiasts for their unique beauty when cut and polished. Uses: Jewelry and Art: When cut and polished, the colorful and patterned interiors are used for cabochons, beads, and decorative art pieces. Decorative: Larger specimens are used as display pieces or in home decor. Educational: They provide insights into geological processes and are used in educational settings to teach about mineralogy and volcanology. Considerations: Variability: Each thunderegg can be quite different, even from the same bed, making them unpredictable and exciting to collect. Cutting and Polishing: To reveal their beauty, thundereggs must be cut, which requires special equipment like a rock saw and polisher. Ethical Collecting: Due to their popularity, collectors should be aware of legal regulations regarding collecting, especially on public lands or private property. Thundereggs are not only a marvel of natural geology but also a testament to the complex interplay between volcanic activity and subsequent mineral deposition, offering both scientific value and aesthetic pleasure.
  1. Whole & Broken Geodes!
    0:58
  2. Geode Field!
    0:59
  3. Botryoidal cut!
    0:58
  4. Shaping!
    0:55
  5. Broken Thunderegg Cluster!
    0:35
  6. Half a thunderegg!
    0:52
  7. Thunderegg Cluster w Common Opal!
    0:41
  8. Red Thunderegg Shard!
    0:42
  9. Thunderegg Cut!
    0:59
  10. Thunderegg Inspection!
    0:28