Mineral deposits in our bodies (teeth and bones) are pretty good.

In non-replicating cells DNA would be pretty good too. Some of it gets replaced as repairs occur, but most of it would not. I'm not sure that carbon dating would be very accurate over the lifetime of a person (though specific events could cause specific sorts of deposits in bones during the occurrence of those events). And even if it was, radioactive carbon, either because of damage, or because of electrochemical effects, would probably be replaced in DNA more frequently than non-radioactive carbon, as long as the organism was alive, even in non-replicating cells.

This doesn't hold true for all cell types. There's a group in Sweden that has C14 dated the replication rate of some cell types. IIRC some cell types - some neurons and adipocytes - only replicate every 10 years or less. Their method has something to do with C14 from nuclear weapons: people who lived before they went off wouldn't have as much. And a lot of C14 would be from the uptake of nuke C14 since. IIRC pre-nuke people have adipocytes with C14 amounts compared to post-nuke people because those cells barely divide. That's what I picked up from a talk way back. I believe this is the same group. https://news.ki.se/new-neurons-generated-in-the-hippocampus-...