Abstract:
This study aimed at evaluating Matisaa gray rock (MGR) for clinker production. MGR is naturally
abundant in Matisaa, a rural area in Mwingi West District, Kitui county, Kenya. It is locally used as
a gabion filler and other concrete structures with desirable physico-mechanical properties. This
research employed a controlled experimental design to determine the clinker qualification of MGR.
This was based on particle size analysis and raw meal moduli. The standard sieve tests and a
Blaine meter were used in the determination of particle size while the raw meal moduli were
determined from the respective cement oxides in MGR, which were determined using wavelength
dispersive X-ray fluorescence (WDXRF) spectrometer. It was observed that 69.65% of the particle
size composition of MGR was less than 90 µm. Out of this composition, 71.60% of the particle
sizes were less than 45 µm, contributing to a specific surface area of 292.5 2 -1 m kg . The hydraulic
modulus (2.05 – 2.61) and lime saturation factor (0.87 – 0.98) are quite desirable though the silica
and alumina ratios are higher than the standard range due to the low proportions of Fe O2 3 and Al O2 3
