铁锰结核中锰矿物的微观特征一直是学术界研究的热点。锰矿物的微观特征包括锰矿物的晶体结构和元素在锰矿物中的赋存状态。成岩型铁锰结核中的锰矿物主要有钙锰矿、布塞尔矿和水钠锰矿等；水成型铁锰结核中的锰矿物主要是水羟锰矿。钙锰矿的晶体结构是隧道结构；布塞尔矿、水钠锰矿和水羟锰矿的晶体结构都是层状结构。铁锰结核中锰矿物一般含有过渡金属元素(Co、Ni、Cu、V、Mo、W和Pt)和稀土元素(La、Ce、Pr、Nd、Pm、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Y和Sc)。过渡金属元素的富集现象是专属吸附和选择性吸附的结果，它们能与锰矿物形成稳定的内圈配合物。目前，一般认为稀土元素主要通过静电引力吸附在锰矿物上。

This is a mini-review paper about microscopic characteristics of manganates in ferromanganese nodules. The manganates in diagenetic nodules are mainly todorokite, buserite and birnessite. The manganates in hydrogenetic nodules are mainly vernadite.The crystal structure of todorokite is tunnel structure. The crystal structure of buserite, birnessite and vernadite is layered structure. Both transition metals (Co, Ni, Cu, V, Mo, W, and Pt) and rare earth elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y and Sc) are enriched in manganates. Mechanisms for enrichment of transition metals are the specialistic adsorption and the selective adsorption. Currently, it is generally believed that rare earth elements are adsorbed by manganates through electrostatic attraction.