Home / Aggregates / 1B Limestone 1B Limestone 1B Limestone is a crushed limestone, approximately 1/4″ to 1/2″ in diameter. It is most commonly used for driveways, fire pits, and pathways. Category: Aggregates Product ID: 17905 Related products Black Mulch Limestone #9 Brown Mulch River Stone 1B | Pea Gravel