I've read a lot about diatomaceous earth being useful for organic gardening, animal raising, pest control, intestinal parasite treatment, etc. However I am somewhat conflicted about the material itself - from what I understand it's essentially ground plankton fossil. How sustainable is this? Will there be "peak diatomaceous earth"?
A similar question was raised on Australia's Garden Web forum, with one poster making a pertinent point that they do not believe that the
use of any natural resource that's not renewable in our lifetime can be considered sustainable.
This is the key point, from a supplier website information page Diatomaceous Earth online describes that the formation of the parent rock Diatomite takes several millions of years, specifically
DE, or fresh water amorphous silica, was formed from the remains of Diatoms which lived in ancient freshwater lakes. These tiny ancient algae had a glassy cylindrical structure which were deposited on the lake bottom over millions of years to form Diatomite.
Further, a report from the New South Wales Department of Primary Industries, Diatomite indicate that there are plentiful resources in several countries, suggesting the 'peak-diatomaceous earth" is not a major concern at this stage. Also, there are many abundant alternatives for the uses of diatomaceous earth.
However, having said all that, the fact that the material is the fossilised remains from up to 65 million years ago (according to the above website) that undergo a geochemical process that takes considerable time (compared to a human lifespan), then it is not truly sustainable, especially as stated by the International Diatomite Producers Association website:
There are many diatomite deposits throughout the world, but those of high-purity which are commercially viable are rare.
I disagree with Helios's answer.
If you are going to rule out anything non-renewable in our lifetime, then we are constrained to a wood and plant society. Can't even chip flint arrowheads by that standard.
I have trouble when a resource whose transport costs more than the material itself is called 'rare' and whose primary use is filtering beer, pool water, and making kitty litter. (Diatomite in the US at the mine gate goes for about 10 cents a pound)
It will be like iron. The easily accessed high grade ore in the Mesabi range is worked out. Now we make iron (and make it cheaper) with 10% ore than we did with the nearly pure Hematite ore a hundred years ago.
Commercially viable also is linked to location. A deposit 50 miles from the nearest paved road is not viable. (The total US market was under $200,000,000. If you got 10% of the market it will take a looooonnnnnnnnnng time to pay for your road.)
Finally while the present deposits were made X million years ago, diatoms still thrive in both fresh and ocean waters. They still die, and their shells stack up on the water's bottom. You can't see the diatomaceous earth that formed last week. But you can't see America drifting away from England either.
Here's a substitute for it's use as a water filter:
For a general search for alternatives try googling diatomite alternatives