# manganese nodule

> rock concretion on the sea bottom made of layers of iron/manganese hydroxides

**Wikidata**: [Q939579](https://www.wikidata.org/wiki/Q939579)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Manganese_nodule)  
**Source**: https://4ort.xyz/entity/manganese-nodule


## References

1. Freebase Data Dumps. 2013