Abstract: The Başören area is located about 670 km. southeast of capital Ankara, within northwest margin of the eastern Tauride belt. Inthe studied area the principal rock units are; Karapınar Limestone (Upper Cretaceous), Kızılkaya ophiolites (Upper Cretaceous),Ardıçh syenitoids (Upper Cretaceous-Lower Paleocene), Alibeyli carbonatites (Middle-Upper Paleocene), Başören formation(Middle-Upper Eocene), Kepez volcanites (Middle-Upper Miocene).Karapınar limestone is overthrusted by ophiolites during Upper Cretaceous. Hie limestones are also intruded by syenitoids. Thecontact between limestones and syenitoids are abrupt. No contact metamorphism has been observed. The syenitoids are intruded bycarbonatites. Two varieties of carbonatite have been distinguished.The aegirine-fluorite-apalile carbonatite (CI) and fluorite-apatitecarbonatite (C2). Fertilization in syenitoids are caused by carbonatite emplacement. Başören formation is represented by conglomerate, sandstone and limestone. Kepez volcanites are represented by andesitic lava and pyroclastics and olivine basaltic lava.Britholite (/?ZsZs,Ca,Na)5[(Si,P)04]3 (OH,F) veinlets are confined to carbonatites. The mineral is thorian member. Britholite occurs in the form of fine grain aggregates. It is dark brown, has greasy luster, and empirical d=4,5669 gr/cm3` The optical propertiesare £= 1.771, W= 1.774, uniaxial negative. Chemical analyses reveal that the britholite has % 57,13 REO and %2.68 ThO->. Microprobe analyses of britholites reveal an empirical formula of;(^0,869 Cg 1,392 ^r0,U8 ^0,324 ^m0,060 ^0,030 ^0,168 `^l0,084 ^a 1,826 ^a0,040 0,08^ (^2,804 ?0.154 l-J0,042^(^ 12^ (OH lM F0()3)Britholites are assocciated with late stage fluorite-apatite carbonatite (C2) dykes injected during last stage of carbonatite intrusion.