Changes

* '''Accessory minerals''' make up a small percentage of the grains in a sandstone. They commonly include micas such as muscovite and biotite, olivine, pyroxene, and corundum, zircon, tourmaline, rutile, garnet, magnetite, or other dense, resistant minerals derived from the source rock.

* '''Accessory minerals''' make up a small percentage of the grains in a sandstone. They commonly include micas such as muscovite and biotite, olivine, pyroxene, and corundum, zircon, tourmaline, rutile, garnet, magnetite, or other dense, resistant minerals derived from the source rock.

* '''Matrix''': is very fine material present within interstitial pore space between the rock grains. Sandstones are often classified on basis of amount of matrix into Arenites (quartz arenite, lithic arenite and feldspar arenite); which are texturally clean sandstones that are free of or have very little matrix, and Wackes are texturally dirty sandstones that have a significant amount of matrix.

* '''Matrix''': is very fine material present within interstitial pore space between the rock grains. Sandstones are often classified on basis of amount of matrix into Arenites (quartz arenite, lithic arenite and feldspar arenite); which are texturally clean sandstones that are free of or have very little matrix, and Wackes are texturally dirty sandstones that have a significant amount of matrix.

* '''Cement''': is a secondary mineral that forms after deposition and during burial of the sandstone and binds the siliclastic framework grains together. Cements mainly include carbonate, clay minerals and silica cements and Other minerals that act as cements include: hematite, limonite, feldspars, anhydrite, gypsum, barite, clay minerals, and zeolite . Silica cement can consist of either quartz or opal minerals. In sandstone where there is silica cement present the quartz grains are attached to cement, this creates a rim around the quartz grain called overgrowth. The overgrowth retains the same crystallographic continuity of quartz framework grain that is being cemented. However Opal cement often occurs in sandstones rich in volcanogenic materials, and very rarely is in other sandstones. Calcite cement is the most common carbonate cement. Calcite cement is an assortment of smaller calcite crystals. The cement adheres itself to the framework grains, this adhesion is what causes the framework grains to be adhered together.

* '''Cement''': is a secondary mineral that forms after deposition and during burial of the sandstone and binds the siliclastic framework grains together. Cements mainly include carbonate, clay minerals and silica cements and Other minerals that act as cements include: hematite, limonite, feldspars, [[anhydrite]], [[gypsum]], barite, clay minerals, and zeolite . Silica cement can consist of either quartz or opal minerals. In sandstone where there is silica cement present the quartz grains are attached to cement, this creates a rim around the quartz grain called overgrowth. The overgrowth retains the same crystallographic continuity of quartz framework grain that is being cemented. However Opal cement often occurs in sandstones rich in volcanogenic materials, and very rarely is in other sandstones. Calcite cement is the most common carbonate cement. Calcite cement is an assortment of smaller calcite crystals. The cement adheres itself to the framework grains, this adhesion is what causes the framework grains to be adhered together.

* '''Pore space''': consists of open spaces within the sandstone and has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together.

* '''Pore space''': consists of open spaces within the sandstone and has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together.