High compression strength and high ductility spherical nanoballs were produced by electric arc discharge with a carbon electrode containing silicon, oxygen, potassium, and sodium. Compression tests of the nanoballs were conducted by application of a load to nanoballs inserted between two polished sample stages with nanolevel surface roughness. Experimental estimation of the compression strength of nanomaterials was enabled by careful selection and polishing of the sample stage materials. (C) 2009 Elsevier B. V. All rights reserved.