A method of making a high-purity semiconductor grade granular silicon composition is disclosed. Commercial quantities of the granular silicon can be produced by depositing silicon on silicon seeds in a first chemical vapor deposition (CVD)reactor, thereby growing the seeds into larger secondary seeds. Additional silicon is deposited on the secondary seeds in a second CVD reactor by flowing a gas comprising at least about 7 mole percent of a silicon compound through the second reactor. Dust is reduced in a third reactor. The methods disclosed herein can be used to achieve higher throughput and better yield than conventional practices.