Turquoise Gravel An intense aquamarine turquoise color make these boulders the rarest item in landscaping. Idaho and Utah quartzite quarries produce this one of kind green rock in North America. It is like having a field or stream of little gem stones in your garden and landscape. Shipped in supersacks. This crushed rock material is the result of quarry larger material from landscape rubble to boulders that also are shipped palleted through the United States.