Earth Science Lab Work

1.  Igneous Grain  visibility Texture/composition Name Properties

Grains  are  Obvious Quartz  Present Granite

Large  grained;  peachy-­‐pink  grains  of  orthoclase   and  the  transparent  grains  of  quartz

Quartz  Absent Diorite Similar  to  granite,  but  not  orthoclase  or  quartz Glassy Obsidian Black;  glassy  texture

Vesicular  (porous) Scoria Dark  in  color;  porous

Grains  aren't  Obvious Pumice Light  in  color;  porous

Fine  grains Basalt Dark  gray-­‐black;  only  very  small  crystals  visible Rhyolite Peachy-­‐pink;  only  very  small  crystals  visible

2.  Sedimentary Grain  visibility Grain  size Grain  type Name Properties

Grains  are  not  Shells Breccia Large  angular  grains

Grains  are  Large Conglomerate Large  rounded  grains

Grains  are  Shells Fossiliferous  Limestone   Fossils  imbedded  in  considerable  matrix

Grains  are  Visible Coquina Fossils  imbedded  in  very  little  matrix

Grains  are  Not  Large Sandstone Sand  grains

 Shale Thinly  bedded Grains  are  not  Visible Chert Very  smooth  and  angular

Petrified  Wood Characteristics  of  wood  preserved

3.  Metamorphic Grain  visibility Banding Name Properties

Banding  Present  Gneiss Grains  align  in  bands

Grains  are  Visible Marble Granular;  will  effervesce  in  acid Banding  Absent Phyllite Fine,  but  visible  grains

Garnet  schist Large,  12-­‐sided  garnets  imbedded  in  matrix Grains  are  not  Visible Slate Dark  colored;  flat  on  top  and  bottom