A wiresaw cutting fluid composition of the present invention comprises about 25 to about 75% by weight of a particulate abrasive suspended in an aqueous carrier containing a polymeric viscosity modifier that comprises a polymer including a majority of non-ionic monomer units (preferably 100 mol % non-ionic monomer units), has a number average molecular weight (Mn) of at least about 5 kDa, and is present in the composition at a concentration sufficient to provide a Brookfield viscosity for the composition in the range of about 50 to about 1000 cP, e.g., 50 to about 700 cP, at about 25° C. at a spindle rotation rate of about 60 rpm. In one embodiment, the viscosity modifier comprises a polymer having a weight average molecular weight (Mw) of at least about 200 kDa. When a viscosity modifier of 200 kDa or greater Mw is utilized, a preferred wiresaw cutting method the cutting fluid is circulated and applied by pumps and nozzles operating at a relatively low shear rate of not more than about 104 s−1.