Sequential reaction textures in Archaean garnet-corundum-sapphirine granulites from the Central Zone of the Limpopo Belt document a progression from early, coarse-grained, high-pressure (P '9.5 kbar) granulite-facie assemblages (Ml) to late, low-pressure (P < 6 kbar) granulite-facies sub-assemblagesThe stable M1 assemblage was garnet (57% pyrope; Mg/(Mg + Fe) = 62) + sapphirine + corundum + gedrite+phlogopite+rutile. Late-M1 boron-free kornerupine grew at the expense of garnet and corundum, and coexisted with garnet, sapphirine and gedrite. Partial or complete breakdown of coarse garnet and komerupine during h42 resulted in the development of pseudomorphs and coronas consisting of fine-grained symplectic intergrowths of cordiente, gedrite and sapphirine (later, spinel).The majority of reaction textures can be explained in terms of a stable reaction sequence, and a model time-sequence of mineral facies can be constructed. When compared with a qualitative petrogenetic grid of (Fe, Mg)-discontinuous reactions in the FMASH multisystem sapphirine-garnet-corundum-spinelcordierite-gedrite-kornerupine, the facies-sequence indicates decompression at essentially constant T assuming constant u(H,O).Exhumation of M1 corundum inclusions during A42 breakdown of kornerupine resulted in production of metastable spinel by a disequilibrium reaction with gedrite. A second disequilibrium reaction of the spinel with cordierite produced sapphirine. The operation of such reaction while pressure was decreasing (the opposite dP from that implied by the texture if assumed to be the product of an equilibrium reaction) has serious implications for the use of reaction textures in the construction of P-T vectors.Garnet-biotite thermometry on garnet interiors and phlogopite inclusions in corundum yields temperatures of cu. 850" C for the M1 stage. A minimum late-M1 pressure of cu. 7 kbar is indicated by the former association of kornerupine and corundum. Relict M1 kyauites reported by other workers indicate a minumum early-Ml pressure of 9.5 kbar, implying metamorphism at depths of at least 33 km (probably ~3 8 k m ) . The high-pressure granulite-facies metamorphism was followed by an almost isothermal pressure decrease of >5 kbar, indicative of rapid uplift. The P-7' path is interpreted as the product of a single metamorphic cycle which probably took place in response to tectonic thickening of the crust. Such a process contrasts with the extensional origin recently proposed for isobaridly cooled granulite-facies terranes.