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Calc-silicates have proved to be important rock types to place constraints on the fluid behaviour in high grade metamorphic rocks. Here we describe amphibolite facies calc-silicate rocks of Wadi Solaf, Egypt which is one of the highest grade basement complexes of Egypt and was exhumed in close connection with the Najd fault system - one of the largest pre-Mesozoic fault systems on the Earth. Calc-silicates formed around 7-8 kbar in temperature range of 600-720 degrees C and can be classified into three groups (CS1, CS2 and CS3). CS1 and CS2 are characterized by the presence of garnet porphyroblasts which contain concentrically arranged wollastonite inclusions. CS3 has a similar paragenesis but is characterized by the presence of clinozoisite/epidote and the absence of wollastonite as well as a pervasive late overgrowth of prehnite. Garnet in CS1 lies along a grossular-andradite solid solution, while the garnet composition of CS2 and CS3 is hydrogrossular and hydroandradite. There is a positive correlation between Al2O3 and Na2O as well as between Al2O3 and Fe2O3 from CS2 through CS1 to CS3 possibly indicating a successive increase in fluid flow between the different calc-silicate types. During the peak metamorphism, the XCO2 is 0.02-0.08 and 0.2-0.44 for the CS1 and CS3, respectively. The mineral assemblage of CS1 and CS2 buffered the composition of the fluids along the reaction: q + cc = wo + CO2. During post-peak metamorphism the rocks were intruded by syn-tectonic granites. CS2 records the contact metamorphic conditions. The rocks reached a peak contact metamorphism conditions at temperature 790-828 degrees C and XCO2 = 0.22-0.41. Finally, the rocks reached a temperature range 296-311 degrees C during the cooling path. (C) 2010 Elsevier Ltd. All rights reserved.