In case you have never seen one, these are manganese nodules. The photo at the front is what the sea floor looks like where these form. : r/geology
General : Maganese Nodules from the Pacific Ocean
Manganese Nodule - an overview | ScienceDirect Topics
Manganese Nodule - Minerals For Sale - #1252224
Polymetallic nodules stay out of the mud with a little help from benthic burrowers. – DSM Observer
MineralMan.com - The Photo Archive of Sold Specimens
Manganese Nodule - Minerals For Sale - #1252228
MineralMan.com - The Photo Archive of Sold Specimens
Manganese Nodule - MRZ100 - deep-sea vent - Atlantic Ocean Mineral Specimen
Nodules - The Metals Company
Manganese nodule hi-res stock photography and images - Alamy
![Manganese Nodule [75442] Pacific Ocean Floor Mining 38 grams](https://cdn11.bigcommerce.com/s-ijipkdz2cc/images/stencil/500x500/products/214/1780/Manganese-nodule-75442-front__13112.1699316988.jpg?c=1 "Manganese Nodule [75442] Pacific Ocean Floor Mining 38 grams")
Manganese Nodule [75442] Pacific Ocean Floor Mining 38 grams
The Race Is On to Mine the Deep Ocean, But Scientists Are Wary
Rhodonite Mineral Specimen For Sale
Manganese Nodule - Minerals For Sale - #3521167
Polylmetallic Nodules - Stock Image - E425/1163 - Science Photo Library
Manganese nodule – Earth-logs
What's In a Nodule?: 2021 North Atlantic Stepping Stones: New England and Corner Rise Seamounts: NOAA Ocean Exploration
![Manganese Nodule Large [86079] 86.76 grams](https://cdn11.bigcommerce.com/s-ijipkdz2cc/images/stencil/1280x1280/products/218/2011/manganese-nodule-86079-front__53382.1707330504.jpg?c=1 "Manganese Nodule Large [86079] 86.76 grams")
Manganese Nodule Large [86079] 86.76 grams
MineralMan.com - The Photo Archive of Sold Specimens
e-Rocks Mineral Auctions
![Polymetallic Manganese Nodule [75681] 36 grams](https://cdn11.bigcommerce.com/s-ijipkdz2cc/products/213/images/1779/Manganese-nodule-75681-front__12871.1699315435.386.513.jpg?c=1 "Polymetallic Manganese Nodule [75681] 36 grams")
Polymetallic Manganese Nodule [75681] 36 grams
Manganese Nodule - Minerals For Sale - #1252221
The Race Is on to Mine and Protect the Deep Seafloor | Scientific American
Potato-shaped sea nodules exceed legal radiation limits
Manganese nodules hi-res stock photography and images - Alamy
