Patent ID: 7919183

Claim:
A coated particle comprising: an inorganic material substrate, wherein the inorganic material substrate comprises silica and alumina in a silica to alumina weight ratio of about 2.2 to about 5; and wherein the inorganic material substrate has a bulk density of less than or equal to about 1 g/cm 3 ; and a coating disposed upon the inorganic material substrate, wherein the coating particle has an apparent density of about 1 to about 2 g/cm 3 , a bulk density of less than or equal to about 1.0 g/cm 3 , an acid solubility of less than or equal to about 6 wt %, a roundness of about 0.7 to about 0.9, a sphericity of about 0.7 to about 0.9, and a crush test percentage of less or equal to about 6% at 2,000 pounds per square inch.