Abstract: A plurality of particles of abrasive particles, wherein at least 1% of the abrasive particles of the plurality of abrasive particles can have a first shape, wherein the first shape includes a body including a first surface having a rounded contour, a second surface joined to the first surface at a first edge, the second surface having a less rounded contour than the first surface, and a third surface joined to the first surface at a second edge, the third surface having a less rounded contour than the first surface. The plurality of particles can further comprise an average particle size of at least 300 microns and not greater than 900 microns, a specific surface area of at least 0.04 m2/g and not greater than 0.10 m2/g, and an alumina content of at least 65 wt % based on a total weight of the plurality of particles.

Abstract: A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

Abstract: A roofing product can include roofing granules, wherein the roofing granules include base particles and a coating covering the base particles. The base particles are sintered. The coating has a depth of penetration into an outside surface of at least about 0.5% of an average radius of the base particles. In an embodiment, the coating has a depth of penetration into an outside surface of at least about 2.5 microns into the base particles. Further included is a process of forming the roofing granules.

Abstract: A proppant for use in fracturing geological formations is made from bauxitic ores and a calcium containing compound. The proppant has a calcium containing crystalline phase.

Abstract: A roofing product can include roofing granules, wherein the roofing granules include base particles and a coating covering the base particles. The base particles are sintered. The coating has a depth of penetration into an outside surface of at least about 0.5% of an average radius of the base particles. In an embodiment, the coating has a depth of penetration into an outside surface of at least about 2.5 microns into the base particles. Further included is a process of forming the roofing granules.

Abstract: A roofing product can include roofing granules, wherein the roofing granules include base particles and a coating covering the base particles. The base particles are sintered. The coating has a depth of penetration into an outside surface of at least about 0.5% of an average radius of the base particles. In an embodiment, the coating has a depth of penetration into an outside surface of at least about 2.5 microns into the base particles. Further included is a process of forming the roofing granules.

Abstract: A proppant for use in fracturing geological formations is made from bauxitic ores and a calcium containing compound. The proppant has a calcium containing crystalline phase.

Abstract: Disclosed is a population of ceramic particles that includes a plurality of individual, free flowing particles. The plurality has a total weight and particle size distribution. The effective width of the distribution is the difference between the distribution's d95 and d5 particle sizes. The distribution's effective width exceeds 100 microns and includes three abutting and non-overlapping regions that include a first region, a second region, and a third region. The first region abuts the second region and the second region abuts the third region. The width of the second region is at least 25% of the effective width. The weight of particles in the second region does not exceed 15% of the plurality of particle's total weight. The weight of particles in the first region and the third region each exceed the weight of particles in the second region. Methods of making the populations of ceramic particles are also disclosed.

Abstract: Disclosed is a process for producing ceramic particles, such as proppants, that have at least 10 percent total porosity. The process includes forming a particle precursor that includes 5 percent to 30 percent of a first ceramic material and at least 40 percent of a second ceramic material. The sintering temperature of the first ceramic material may be lower than the sintering temperature of a second ceramic material. Heating the precursor to a maximum temperature above the sintering temperature of the first material and below the sintering temperature of the second material. Also disclosed is a ceramic article that has a particular combination of chemistry and alumina crystalline phase.

Abstract: A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

Abstract: A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

Abstract: Disclosed is a process for producing ceramic particles, such as proppants, that have at least 10 percent total porosity. The process includes forming a particle precursor that includes 5 percent to 30 percent of a first ceramic material and at least 40 percent of a second ceramic material. The sintering temperature of the first ceramic material may be lower than the sintering temperature of a second ceramic material. Heating the precursor to a maximum temperature above the sintering temperature of the first material and below the sintering temperature of the second material. Also disclosed is a ceramic article that has a particular combination of chemistry and alumina crystalline phase.

Abstract: A ceramic particle with at least two microstructural phases comprising an amorphous phase, representing between 30 volume percent and 70 volume percent of the particle, and a first substantially crystalline phase comprising a plurality of predominately crystalline regions distributed through the amorphous phase is disclosed. A process for making the ceramic particle is also disclosed.

Abstract: A roofing product can include roofing granules, wherein the roofing granules include base particles and a coating covering the base particles. The base particles are sintered. The coating has a depth of penetration into an outside surface of at least about 0.5% of an average radius of the base particles. In an embodiment, the coating has a depth of penetration into an outside surface of at least about 2.5 microns into the base particles. Further included is a process of forming the roofing granules.

Abstract: Disclosed is a population of ceramic particles that includes a plurality of individual, free flowing particles. The plurality has a total weight and particle size distribution. The effective width of the distribution is the difference between the distribution's d95 and d5 particle sizes. The distribution's effective width exceeds 100 microns and includes three abutting and non-overlapping regions that include a first region, a second region, and a third region. The first region abuts the second region and the second region abuts the third region. The width of the second region is at least 25% of the effective width. The weight of particles in the second region does not exceed 15% of the plurality of particle's total weight. The weight of particles in the first region and the third region each exceed the weight of particles in the second region. Methods of making the populations of ceramic particles are also disclosed.

Abstract: A sintered ceramic particle made from a ceramic material having a true density greater than 3.5 g/cc and a composition having no more than 30 weight percent silicon oxide and at least 15 weight percent iron oxide, based on the combined weight of the oxides of aluminum, iron and silicon, is disclosed. A process that utilizes an externally applied compressive force to make a ceramic particle is also disclosed.

Abstract: One embodiment of the present invention relates to spherical ceramic elements, such as proppants, for maintaining permeability in subterranean formations to facilitate extraction of oil and gas therefrom. The strength of the ceramic element may be enhanced by combining materials having different coefficients of thermal expansion. Methods of making the ceramic elements are also disclosed.

Abstract: One embodiment of the present invention relates to spherical ceramic elements, such as proppants, for maintaining permeability in subterranean formations to facilitate extraction of oil and gas therefrom. The strength of the ceramic element may be enhanced by combining materials having different coefficients of thermal expansion. Methods of making the ceramic elements are also disclosed.

Abstract: One embodiment of the present invention relates to spherical ceramic elements, such as proppants, for maintaining permeability in subterranean formations to facilitate extraction of oil and gas therefrom. The strength of the ceramic element may be enhanced by combining materials having different coefficients of thermal expansion. Methods of making the ceramic elements are also disclosed.

Abstract: A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.