  Ball-milling graphite was conducted in miscible solutions with the purpose to
exfoliate graphene. Colloid-like stable supernatants were unexpectedly
obtained. Followed were the characterizations with Scanning electronic
microscopy, Thermogravimetric analysis, X-ray diffraction and Elemental
dispersive X-ray mapping to recognize them. As a result, strongly against the
initial judgments, the components of colloid were mainly impurities of mixture
of zirconia, silicate and yttrium oxide, other than nano-graphite.
