1.8# Silicified Sponge Fossil Stromatoporoid Calcareous 02"x6.5"x6.25" Agate For Sale

• We are changing our payment policy to help anyone wanting to take advantage of it. Instead of requiring immediate payment when using Buy It Now, you will have up to 4 days to make payment. After that time, items still awaiting payment will be canceled.

• Please click on Seller's other items on previous page to see our Store.

• Combined Shipping: Please send us the item numbers you're wanting to purchase. The purpose of doing this, we can normally cut down the expense of shipping multiple items. (Combine multiple items in one box). We can do this on most items, except the largest of our items. Example: XX-Large Driftwood, XXX-Large Driftwood. Thank You

• We are a (Top Rated Plus) vendor awarded here on E-bay for stellar Customer service. (Top 3% awarded this seal!)
  
• Thousands of items sold here on e-bay, member beginning in 2000 (find another driftwood vendor longer than us!)
• Shop with 100% confidence.
  
• Please click on other items or feel free to visit our E-bay store, Thank You.

Located in Northern Middle Tennessee, each piece is selected for its individuality and aesthetics. Unsurpassed, each piece is a testament to the beauty of nature.This particular piece is called Stromatoporoid Sponge, an extinct group of sponges that formed a hard compact skeleton. Stromatoporoids lived only in seawater, and like modern sponges, they created currents to pump water in and out of their body, where they filtered out tiny food particles. Stromatoporoids were a major type of reef constructor.
Stromatoporoids are considered to be calcareous sponges. They are bottom-dwelling, nonmobile marine invertebrate animals that built skeletons with thin layers of calcium carbonate and form mounds on the seafloor.
Ancient stromatoporoids thrived in warm clear, shallow marine waters. During the Devonian Period 450 million years ago here in Tennessee.
Silicified sponge happens when the original calcium carbonate of an ancient sponge skeleton is slowly dissolved and replaced by silica (quartz) molecules from groundwater. This process, which can take millions of years, preservers the sponge internal structures in a durable gemstone like form.
Step -by-Step Process

• Burial and Sedimentation-Ancient sponge dies and is rapidly buried under layers of sediment (like sand and mud) in a shallow marine environment. This burial prevents the sponge from being completely eaten or broken down by ocean currents.
• Dissolution by Groundwater- As the surrounding sediments turn into sedimentary rock (like limestone), underground water saturated with silica percolates through. The acidic groundwater slowly dissolves the original, fragile calcium carbonate skeleton, creating microscopic empty voids.
• Silica Replacement- Almost exactly as the old sponge material dissolves, the dissolved silica precipitates out of the groundwater and fills the empty spaces. This can happen by Silicification Replacement- The silica replaces the sponge structure cell-by cell. This incredibly detailed process preserves delicate internal walls and ridges.
• Because quartz is much harder and more resistant to weathering than the surrounding limestone, these fossils can often be found eroding out of creek beds.

THIS PARTICULAR PIECE IS A SILICIFICATION SPONGE FOSSIL.You will not find another piece so detailed and intact, from the Ordovician period-450 million years ago, unless you are a collector or a Museum.
Tennessee was completely submerged beneath a warm shallow sea,200 Million years before Dinosaurs.
Silicified Sponge is perfectly safe for both freshwater and saltwater aquariums. Because the original calcium carbonate has been replaced by quartz, it is inert and will not alter your water chemistry. These pieces will also look great in decorating your aquarium room outside the tanks. The sparkle of the exposed quartz of some pieces are amazing!
Collectors of Rocks, Crystals, and Mineral Specimens will also love these pieces for display. Also great for office decor. Each Sponge piece has been thoroughly cleaned to ensure the utmost beauty. All Sponge fossils are washed with tap water only. Golf ball in photos shows size comparison.We take extra care when packing our rocks. Extra bubble wrap, packing material, double and triple wall boxes. .
Size Inches: H-02,L-6.5,W-6.25 Weight: 1.8 pounds Stock # 181209 B121008