seashells considered recycled content?

Dan - In order for the manufacturer to claim post-consumer recycled content for seashells, consumers would have discarded the shells. Have you considered asking the other manufacturer about the source of the seashells?

Maybe other LEEDusers have some insights?

...maybe if you look at the crustacean that once lived in it, as the original consumer? )

But you have to remember that the crustacean also built the shell. How do you establish the labor costs so you can properly report the material values? :)

...yes, not to mention that tricky "Sand Dollar" to US dollars conversion. )
but getting back to the original question, if the shells had been used as a fill material, or in some sort of landscaping scheme first, I guess that would be post consumer. Probably the best thing to do is ask the manufacturer about the source of the shells.

I did find one reference online about a “Mediterranean Plaster" technique that uses seashells recycled from the sea food industry...would LEED see that as post consumer?

I think we need to research the animal products in LEED Interpretations. My basic understanding is that if the animal survives, then it can count. But if the animal does not, then it isn't counted as sustainable material in LEED. There should be better conversations about that in the NCv3 MR credit 6 boards.

Interesting question. I previously advised someone that shells would not be considered rapidly renewable.But I would see a reasonable case for shells from the seafood industry being post-consumer recycled. There is no perverse consideration around whether a dead animal is "rapidly renewable." It could just be considered a technical matter of defining the place of the shells in the waste stream.

Susan & Tristan raise a good point about MRc6 excluding certain animal products. However, LI#2549, the Ruling that established this demarcation, dealt exclusively with the definition of "Rapidly Renewable Materials," not recycling. Nothing else in LEEDv3 Reference Guides or addenda to extend this Ruling to other MR Credits. Even LEEDv4 only excludes animal hide from its “Bio-Based” definitions, not from other sustainable criteria. Finally, the recycled content definitions in ISO-14021 do not exclude animal products. Unless USGBC issues a clarification, nothing seems to prohibit counting seashells as reused, recycled, or regional. Still, you might choose to exclude them on principle.

If you choose to include shell in your MRc4 tally, Michelle & Tristan are right that it would be PRE-consumer if it comes as a byproduct of seafood processing, as Charles suggests. (POST-consumer shells would be those that waiters at an oyster bar clear from the tables after a busy night.) Make your manufacturer justify their claim.

In the end, the point may be no more than an interesting mental/ethical exercise. Unless your project spends huge amounts on terrazzo countertops, the value of the tiny percentage of shell in them would be miniscule compared to the overall budget.