Hey Giles - Iron Oxide reacts with certain natural chemicals to turn black. We've used it in our own denim for Story with myroblan flowers (on top of indigo dyed denim) and the results are super. My black jeans fade to indigo, then ecru which feels very gentle.

We've also done it with Kakishibu (this may be more up your alley) and it's worked well. The only downside is the smell with kakishibu - though I understand you can get some now where it's been removed.

Let me know if I can help otherwise. Natural black is a rare but beautiful thing and we aren't greedy at all about sharing.

Thanks guys. It's been a long slog but it's all been worth it. The denim is indian and we have powerloomed and hand loomed denims. They're all dyed with natural indigo, most hank dyed (in different methods) and the jeans are made up here in the UK.

Every part is made by a craftsman, and there's no exploitation anywhere (if you don't count extortionate import duties we're going to get crushed under).

story mfg. Is mine and my partners brand! I'm a long time lurker here (bought some things off you guys though) and I'm ecstatic to see this posted here!