You Searched For: Specialty Rocks

wardsci.com 800-962-2660 Graywacke Type: Sedimentary; clastic. Texture/Appearance: Generally coarse-grained with angular to sub-angular poorly sorted grains in a clayey matrix. May show graded bedding; fossils are rare. Color: Gray to greenish-gra...

+ward’ssciencewardsci.com800-962-2660 Gneiss Type: Metamorphic; regional. Texture/Appearance: Foliated often with distinct banding (segregation) of minerals; some preferred orientation in micas (platy) or hornblende (prismatic crystals). Medium to...

+ward’ssciencewardsci.com800-962-2660 Schist Type: Metamorphic; regional. Texture/Appearance: Fine to coarse-grained strongly foliated. Granoblastic grading into porphyrob- lastic with mineral segregation banding usually present. Individual minera...

wardsci.com 800-962-2660 Breccia Type: Sedimentary; clastic. Texture/Appearance: Coarse-grained angular rock fragments cemented in a fine- to very fine-grained matrix. Clasts have sharp edges. Color: Variable. Mineralogy/Chemistry: Composition var...

+ward’ssciencewardsci.com800-962-2660 Arkose Type: Sedimentary; clastic. Texture/Appearance: Usually coarse-grained sometimes with pebbles. Angular to subangular poorly to moderately well-sorted sand grains. No Fossils. Color: Gray pink or reddish...

+ward’ssciencewardsci.com800-962-2660 Tuff Type: Igneous; extrusive (pyroclastic). Texture/Appearance: Clastic texture with angular rock and mineral fragments and lapilli mixed with fine-grained volcanic ash partly cemented by sedimentary material...

+ward’ssciencewardsci.com800-962-2660 Conglomerate Type: Sedimentary; clastic. Texture/Appearance: Coarse-grained rock containing rounded to subangular clasts of greater than 2mm in diameter scattered in a finer-grained matrix of sand silt and/or ...

ward’s sciencewardsci.com800-962-2660 Greenstone Type: Metamorphic; regional. Texture/Appearance: Fine-grained massive or compact; generally non-schistose. Color: Dark green. Mineralogy/Chemistry: Mainly composed of chlorite actinolite epidote and...

+ward’ssciencewardsci.com800-962-2660 Diorite Type: Igneous; intrusive. Texture/Appearance: Massive generally medium-to-coarse grained; subhedral equigranular to por- phyritic. Differences in color and grain size are common with orbicular structur...

wardsci.com 800-962-2660 Hornblende (CaNa)2-3 (MgFeAl)5 SI6 (SiAl)2 O22 (OH)2 (Amphibole Group) Crystallography: Monoclinic: 2/m. Crystals prismatic usually terminated by {011}. May be columnar to fibrous; coarse-to fine-granular. Physical Propert...

wardsci.com 800-962-2660 Marble Type: Metamorphic; regional and contact. Texture/Appearance: Fine to coarse-grained; granoblastic to saccharoidal. May appear patched or with streaks or banding that is deformed. Color: Variable commonly white pink ...

+ward’ssciencewardsci.com800-962-2660 Shale Type: Sedimentary; clastic. Texture/Appearance: Very fine-grained (clay to silt-sized particles) grains not distinguishable to the naked eye. A relatively soft rock with fine laminae; may display carbona...

+ward’ssciencewardsci.com800-962-2660 Skarn Type: Metamorphic; contact. Texture/Appearance: Most often coarse-grained and granoblastic with no foliation. Massive structure with zones of mineral concentration. Color: Varies with mineralogy but usua...

wardsci.com 800-962-2660 Serpentinite Type: Metamorphic; regional. Texture/Appearance: Fine to coarse-grained lamellar or mesh-like; massive with frequent zonations and veins. Color: Dark green to black. Mineralogy/Chemistry: Ultramafic; composed ...

wardsci.com 800-962-2660 Coal Type: Sedimentary; organic. Texture/Appearance: Peat is a brownish matted variety of coal consisting of partly decomposed plant remains seen as visible vegetable matter. Lignite is a darker more compact variety with p...

+ward’ssciencewardsci.com800-962-2660 Apatite Ca5(PO4)3(FClOH) Crystallography: Hexagonal; 6/m. Commonly occurs in crystals of long prismatic habit; also in mas- sive to compact masses. Physical Properties: Cleavage: {0001} poor. Fracture conchoid...