Screened Material

When rock is crushed, it makes a dust or fines product as well as the rock itself.  When you by a screened product, it may have as much as 20 to 25 percent crusher fines in it. Customers sometimes refer to this as dirt in there rock. It is NOT DIRT. It is the powder and smaller rock produced that make it through the screening process. This means that if you buy 10 tons of a screened material, it could have as much as 2 to 2.5 tons of fines in it. The softer the rock, the more prevalent the fines will be.

Minus Material

The same screening process is used to make minus material. In minus material, the fines can be as much as 75 percent of the material.  That means that the crusher fines or small pieces of rock will be a higher percentage. In a 10 ton load, 5 to 7.5 tons of the material may be fines, and the balance will be larger pieces of rock, depending on the size of rock you have chosen.  This type of material packs much more than screened rock, and some people think it looks more like a natural desert.  It does not drain well and has a tendency to wash if installed in an area that has heavy run off.

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Rip Rap and River Rock

All the bulk rock products we sell are screened to size. For most of the standard decorative rock this is pretty straight forward. As for the rip rap and Salt River rock, the end product changes dramatically. When you have a screen size of 2 to 6 inches, what will pass through a 6 inch square hole could be eight inches across and sometimes up to 12 to 18 inches in length. Do not assume when you order 3” to 6” rip rap or salt river rock, the rock pieces will be 3” to 6”. If the screen size is a 6” square hole, and the rock will fall through it, it falls into the size range that is stated.  Make sure that you look at the products in our sample area prior to purchasing so there is no confusion about what you are receiving.