gems, garnet, pyralspite garnet, almandine, pyrope, spessartine, garnet geology

A relationship has been identified between garnet composition, determined through gravimetric analysis, and distinct zones within large complex granitic pegmatites. Manganese-rich garnet (MnO 41–27%) is characteristic of inner and replacement zones, while garnets with intermediate Mn–Fe compositions occur in transitional assemblages, and iron-dominant garnets are found in the wall and contact zones. Pure spessartine is typical of replacement and quartz-rich core zones, particularly in pegmatites hosting lithium minerals such as spodumene, lepidolite, petalite, and amblygonite.