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A composition is disclosed consisting essentially of substantially spherical glass particles having a diameter of less than about 25 micrometers. A process is disclosed for producing substantially spherical particles. The process involves providing irregularly shaped glass particles having a predete

A composition is disclosed consisting essentially of substantially spherical glass particles having a diameter of less than about 25 micrometers. A process is disclosed for producing substantially spherical particles. The process involves providing irregularly shaped glass particles having a predetermined particle size, entraining the particles in a carrier gas, feeding the entrained particles into a high temperature zone having a temperature sufficiently above the softening point of the glass to allow surface tension to subsequently spheroidize the particles and having a temperature below the vaporization temperature of the glass. The particles are maintained in the high temperature zone for a sufficient time to convert at least a portion of the particles into droplets without the formation of a substantial amount of filaments affter which the droplets are cooled to form solid spheres having essentially the same particle size as the irregularly shaped particles and a reduced surface area as compared with the irregularly shaped particles.

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A process for producing substantially spherical particles comprising: (a) providing irregularly shaped glass particles having a predetermined particle size of less than about 20 micrometers in diameter; (b) entraining said particles in a carrier gas; (c) feeding said particles into a high temperatur

A process for producing substantially spherical particles comprising: (a) providing irregularly shaped glass particles having a predetermined particle size of less than about 20 micrometers in diameter; (b) entraining said particles in a carrier gas; (c) feeding said particles into a high temperature zone having a temperature sufficiently above the softening point of said glass to allow surface tension to subsequently spheroidize said glass particles and having a temperature below the vaporization temperature of said glass, said high temperature zone being from about 5500°C. to about 17,000°C.; (d) maintaining said particles in said temperature zone for a sufficient time to convert at least about 90% of said particles into droplets without formation of substantial amounts of filaments; and (e) cooling said droplets to form solid spheres having essentially the same particles size as said irregularly shaped particles and a reduced surface area as compared with said irregularly shaped particles.