In the Central Metasedimentary Belt of western Quebec and eastern Ontario, dozens of fluorapatite and phlogopite deposits hosted by varicolored marble were exploited in the early 1900s. We review the literature on four occurrences: Liscombe and Silver Crater in Ontario and Seybold (Moore) and Yates in Quebec. Using the correlative microscopy approach, we report results of high-resolution scanning electron microscopy of selected areas of interest identified in large-area image mosaics of samples from Liscombe and Seybold (Moore). Textural and compositional aspects of the fluorapatite and its entrapped minerals reveal that the dikes of orange to pink calcite formed from a calciocarbonatitic melt of anatectic origin. Gravitational settling of fluorapatite occurred; the movement of slurries of crystals accounts for the striking alignment of crystals. Silicate minerals, fossil remains, and evaporitic intercalations in the precursor limestone account for the variety of minerals produced. Aggressive assimilation of fenitized host rocks by the carbonate melt was locally important. Some prisms of fluorapatite, locally gemmy and glazed, lost their sharp interfacial angles by resorption into the melt. The dikes at the Liscombe and Seybold (Moore) occurrences are poorly blended, as revealed by compositionally distinct generations of fluorapatite and monazite-(Ce), which crystallized sequentially. At the Silver Crater mine, the fluorapatite has been fenitized by alkaline fluid derived from nepheline syenite pegmatites emplaced nearby. The mantle was clearly involved in the waning stages of the Grenville cycle of continent–continent collisions.

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