Rare occurrences of phosphates with beryllium are limited to granitic pegmatites and, exceptionally, to rare-element granites. Primary crystallization is extremely scarce; most of these phosphates form as late subsolidus phases. Paragenetic relationships of these minerals and conditions of their origin are poorly understood. Beryllonite, hydroxylherderite and carbonate-fluorapatite form thin coatings in fissures of beryl in the Archean petalite-subtype BEP pegmatite in southeastern Manitoba. The composition of beryllonite corresponds to its ideal formula, and hydroxylherderite contains only traces of fluorine. The B-type carbonatefluorapatite shows considerably reduced P 2 O 5 content, "excess" fluorine, and an apparently high CO 2 content (estimated at ~5 tõ 7 wt.%). Beryllonite was the first phosphate to precipitate, followed and in part replaced by hydroxylherderite; carbonatefluorapatite rims, penetrates and replaces both preceding phases. Low a(F) is indicated during the formation of beryllonite and hydroxylherderite, but it must have increased to stabilize carbonate-fluorapatite. The process probably involved F released during the (OH)F-1 exchange in the associated montebrasite.