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Yikes... I know coral and other invertebrates are very sensitive to heavy metals like nickel.

We will be testing the sources of olivine for nickel, and as posted upstream, we have potential solutions for phytomining the olivine reserves for nickel with nickel hyper-accumulating plants, and then burning plants, retrieving the nickel ore and using the proceeds it to further fund operations...

I hope you would still run tests to determine how much left over Nickel is getting into the ocean.

Not just coral will be effected by Nickel, but other important invertebrates as well such as amphipods which play an enormous role in the food chain and health of reef environments.

And we’re talking parts per billion (ppb) when heavy metals can start to become toxic.

And correct me if I’m wrong, but Manganese is another element often found in olivine, which is another metal that can be toxic to marine life.

Yes, we plan to not only run tests on every source before placing the olivine on beaches, but to carry out on-going monitoring with sensors. We are looking for experts in this area (and many others) to help design processes to make sure the olivine weathering is purely beneficial to the marine ecosystem (i.e. deacidification, increasing calcium carbonate levels, and boosting diatoms). You seem passionate about this, if you or someone you know can help us with this please sign up here -> https://projectvesta.org/get-involved/

The dose makes the poison, and in the case of manganese (which is, by the way, not a proper noun), the toxic dose is quite large (unless you're inhaling it), to the point where manganese deficiency is a larger public health problem in humans than manganese poisoning. MnO2 and even the soluble manganese sulfate we use for fertilizer are in the same blue-1 classification as things like alcohol and potassium chloride.

Nickel is a more reasonable concern; nickel sulfate's lethal dose is on the order of 250 mg/kg for humans, so around 10 or 15 grams for an adult. It's not really in the same category as things like mercury, lead, thallium, barium, or even cadmium.

Yes, nickel is more of a concern, but manganese is still toxic. Comparing heavy metal toxicity to human lethal doses can be misleading, however.

Invertebrates are much more sensitive to heavy metals. Again toxic doses for many marine invertebrates are in the ppb-ppm range.

Copper for instance is commonly used as a treatment for marine parasites on fish. However the dosing needs to be done carefully, since a doses in the range of 5ppm can start to kill the fish themselves.

Thank you! Yes, I'm pretty sure nickel is more toxic than copper, including to marine organisms. Where can I learn more?

What's preventing the whole operation from going sideways and spewing pollution? With no economic incentive to do it right, and the impact almost impossible to measure, it could quicky devolve into environmentalism theater.

It's basically impossible to save corals at this point. The oceans will become too warm for them.

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