Blue stone dust is referring to a fine crushed bluestone also referred to as blue stone screening. It’s use is for base preparation for roadways and driveways.it is manufactured from the remains of blue stone quarries, any leftover pieces while treads and pavers are manufactured is recycled and crushed in to gravel. This is produced in many sizes from 3 inches rocks to finer dust and the finer dust is called blue stone dust. Main use for this product is? Final grade for base preparation, also used as the top finished layer for a gravel driveway because it is fine and it packs down very well it is also used for the bocce court finished surface and to fill the joints of paving stones when wide gap paving stone pattern are used . for all your stones questions, you came to the long island stone experts.Gappsi can design, supply and install your entire project. To learn more about Gappsi products and services for Nassau and Suffolk county long island NY .Please e mail us at Giuseppe@gappsi.com or call Gappsi at 631-543-1177 or visit Gappsi Show Room at 1015 west Jericho turn pike Smithtown NY 11787 or visit us on line at : www.gappsi.com