

Want to know what possibility for harvesting a particular element is, from the ocean?
click on it in https://www.mbari.org/know-your-ocean/periodic-table-of-elements-in-the-ocean/
( scroll down a bit )
& see a new page open up, identifying how abundant/not it is, & the top-to-bottom-gradient of it…
Rare-earths may be sufficiently harvestable from the ocean using Metal-Organic-Frameworks, for coastal de-salination plants, or tidal-power-plants, if done at scale…
( which would break national-monopolies, wouldn’t it? )
just don’t bother trying to mine iridium through that method: you’ll never get enough to make it worthwhile.




THEN they NEED to have ultrasonic sensors, activated at … say … 1/2-metre intervals, because LIDAR may be blind to float-glass that isn’t at a right-angle to it, but SONAR isn’t blind to sheet-glass.
_ /\ _
( the things might harm the hearing of animals, hence the limiting it to a chirp-every-1/2-metre idea: minimize noise-pollution that we are “blind” to, see? )