**Abstract**

The supergroup of apatite is divided into five groups of minerals. Therefore, minerals from the group of apatite were described in the first chapter, the second chapter of this book continues with description of minerals from the other four groups, i.e. minerals from the group of britholite, belovite, ellestadite and hedyphane. The structure, properties and known localities of these minerals were described. Although carbonateapatite species are discredited from the IMA list of minerals, the chapter ends with description of structure and properties of carbonate-hydroxylapatite, carbonatefluorapatite, and carbonate-rich varieties of apatite, i.e. francolite, dahlite, kurskite and collophane. The introduced three basic types of carbonate-apatites, i.e. type A, B and AB) are then discussed in Chapter 10 in depth.

**Keywords:** Apatite, Britholite, Belovite, Ellestadite, Hedyphane, Carbonate-apatite, Francollite, Dahlite

As was mentioned in **Section 1.1**, the supergroup of apatite is divided into five groups. The most important minerals form the group of britholite (**Section 2.3**), belovite (**Section 2.2**), ellesta‐ dite (**Section 2.4**) and hedyphane (**Section 2.1**), which are described in this chapter together with carbonate fluorapatite and hydroxylapatite (**Section 2.6**).

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**Fig. 1** Distribution of described minerals from the supergroup of apatite (discredited species are also included) among individual groups (a) and distribution of kind of XO4 tetrahedra (b), crystal system (c) and space group (d) among these species.

Other minerals from the supergroup of apatite include 65%, i.e. 28 described mineral species **Fig. 1**(**a**), which predominantly crystallize in hexagonal system (**c**) and in the space group P63/M (**d**).The [PO4] 3−unitis themostfrequent ortho-oxyanionforthe supergroupof apatite ingeneral (**b**), but its content in individual groups varies strongly (**Fig. 2**).

**Fig. 2** Frequency of XO4 ions and point groups for individual groups from the supergroup of apatite.
